<!--- Verify first that your issue is not already reported on GitHub -->
<!--- Also test if the latest release and devel branch are affected too -->
<!--- Complete *all* sections as described, this form is processed automatically -->

##### SUMMARY
<!--- Explain the problem briefly below -->
When using ansible to stop an OpenStack VM, specifying wait=no occur a error.

##### ISSUE TYPE
- Bug Report

##### COMPONENT NAME
<!--- Write the short name of the module, plugin, task or feature below, use your best guess if unsure -->
os_server_action

##### ANSIBLE VERSION
<!--- Paste verbatim output from "ansible --version" between quotes -->
```paste below
ansible 2.8.5
  config file = /etc/ansible/ansible.cfg
  configured module search path = [u'/home/ubuntu/.ansible/plugins/modules', u'/usr/share/ansible/plugins/modules']
  ansible python module location = /usr/lib/python2.7/dist-packages/ansible
  executable location = /usr/bin/ansible
  python version = 2.7.12 (default, Aug 22 2019, 16:36:40) [GCC 5.4.0 20160609]
```

##### CONFIGURATION
<!--- Paste verbatim output from "ansible-config dump --only-changed" between quotes -->
```paste below
no change
```

##### OS / ENVIRONMENT
<!--- Provide all relevant information below, e.g. target OS versions, network device firmware, etc. -->
ubuntu 16.04

##### STEPS TO REPRODUCE
<!--- Describe exactly how to reproduce the problem, using a minimal test-case -->
1. create a openstack vm
2. stop a openstack vm by ansible.
<!--- Paste example playbooks or commands between quotes below -->
playbook
```yaml
- name: Stop an OpenStack instance
  hosts: all
  gather_facts: no
  roles:
    - instance_action
  vars:
    instance_action: stop
```
```yaml
- name: Operate an OpenStack instance action
  os_server_action:
    action: "{{ instance_action }}"
    server: "{{ instance_id }}"
    wait: "{{ wait | default('yes') }}"
    verify: "{{ verify | default('yes') }}"
```
vars
```yaml
instance_id: xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxx
verify: no
wait: no
```

<!--- HINT: You can paste gist.github.com links for larger files -->

##### EXPECTED RESULTS
<!--- Describe what you expected to happen when running the steps above -->
stop a OpenStack vm 

##### ACTUAL RESULTS
<!--- Describe what actually happened. If possible run with extra verbosity (-vvvv) -->
fail to stop a OpenStack vm 
<!--- Paste verbatim command output between quotes -->
```paste below
ansible-playbook 2.8.5
  config file = /etc/ansible/ansible.cfg
  configured module search path = [u'/home/ubuntu/.ansible/plugins/modules', u'/usr/share/ansible/plugins/modules']
  ansible python module location = /usr/lib/python2.7/dist-packages/ansible
  executable location = /usr/bin/ansible-playbook
  python version = 2.7.12 (default, Aug 22 2019, 16:36:40) [GCC 5.4.0 20160609]
Using /etc/ansible/ansible.cfg as config file
host_list declined parsing /etc/ansible/hosts as it did not pass it's verify_file() method
script declined parsing /etc/ansible/hosts as it did not pass it's verify_file() method
auto declined parsing /etc/ansible/hosts as it did not pass it's verify_file() method
Parsed /etc/ansible/hosts inventory source with ini plugin

PLAYBOOK: stop_instance.yml *****************************************************************************************************************************************************************
1 plays in stop_instance.yml

PLAY [Stop an OpenStack instance] ***********************************************************************************************************************************************************
META: ran handlers

TASK [instance_action : Operate an OpenStack instance action] *******************************************************************************************************************************
task path: /home/ubuntu/work/os-integ/roles/instance_action/tasks/main.yml:1
<127.0.0.1> ESTABLISH LOCAL CONNECTION FOR USER: ubuntu
<127.0.0.1> EXEC /bin/sh -c 'echo ~ubuntu && sleep 0'
<127.0.0.1> EXEC /bin/sh -c '( umask 77 && mkdir -p "` echo /home/ubuntu/.ansible/tmp/ansible-tmp-1569828606.07-4717533724530 `" && echo ansible-tmp-1569828606.07-4717533724530="` echo /home/ubuntu/.ansible/tmp/ansible-tmp-1569828606.07-4717533724530 `" ) && sleep 0'
<127.0.0.1> Attempting python interpreter discovery
<127.0.0.1> EXEC /bin/sh -c 'echo PLATFORM; uname; echo FOUND; command -v '"'"'/usr/bin/python'"'"'; command -v '"'"'python3.7'"'"'; command -v '"'"'python3.6'"'"'; command -v '"'"'python3.5'"'"'; command -v '"'"'python2.7'"'"'; command -v '"'"'python2.6'"'"'; command -v '"'"'/usr/libexec/platform-python'"'"'; command -v '"'"'/usr/bin/python3'"'"'; command -v '"'"'python'"'"'; echo ENDFOUND && sleep 0'
<127.0.0.1> EXEC /bin/sh -c '/usr/bin/python && sleep 0'
Using module file /usr/lib/python2.7/dist-packages/ansible/modules/cloud/openstack/os_server_action.py
<127.0.0.1> PUT /home/ubuntu/.ansible/tmp/ansible-local-71929SqXFy/tmpj96ZTW TO /home/ubuntu/.ansible/tmp/ansible-tmp-1569828606.07-4717533724530/AnsiballZ_os_server_action.py
<127.0.0.1> EXEC /bin/sh -c 'chmod u+x /home/ubuntu/.ansible/tmp/ansible-tmp-1569828606.07-4717533724530/ /home/ubuntu/.ansible/tmp/ansible-tmp-1569828606.07-4717533724530/AnsiballZ_os_server_action.py && sleep 0'
<127.0.0.1> EXEC /bin/sh -c '/usr/bin/python /home/ubuntu/.ansible/tmp/ansible-tmp-1569828606.07-4717533724530/AnsiballZ_os_server_action.py && sleep 0'
<127.0.0.1> EXEC /bin/sh -c 'rm -f -r /home/ubuntu/.ansible/tmp/ansible-tmp-1569828606.07-4717533724530/ > /dev/null 2>&1 && sleep 0'
[DEPRECATION WARNING]: Distribution Ubuntu 16.04 on host 127.0.0.1 should use /usr/bin/python3, but is using /usr/bin/python for backward compatibility with prior Ansible releases. A
future Ansible release will default to using the discovered platform python for this host. See https://docs.ansible.com/ansible/2.8/reference_appendices/interpreter_discovery.html for more
 information. This feature will be removed in version 2.12. Deprecation warnings can be disabled by setting deprecation_warnings=False in ansible.cfg.
fatal: [127.0.0.1]: FAILED! => {
    "ansible_facts": {
        "discovered_interpreter_python": "/usr/bin/python"
    },
    "changed": false,
    "msg": "New-style module did not handle its own exit"
}

PLAY RECAP **********************************************************************************************************************************************************************************
127.0.0.1                  : ok=0    changed=0    unreachable=0    failed=1    skipped=0    rescued=0    ignored=0
```

There were the same error at the "start" action.
sdk, cloud = openstack_cloud_from_module(module)
    try:
        server = cloud.get_server(module.params['server'])
        if not server:
            module.fail_json(msg='Could not find server %s' % server)
        status = server.status
        if module.check_mode:
            module.exit_json(changed=_system_state_change(action, status))
        if action == 'stop':
            if not _system_state_change(action, status):
                module.exit_json(changed=False)
            cloud.compute.post(
                _action_url(server.id),
                json={'os-stop': None})
            if wait:
                _wait(timeout, cloud, server, action, module, sdk)
                module.exit_json(changed=True)
        if action == 'start':
            if not _system_state_change(action, status):
                module.exit_json(changed=False)
            cloud.compute.post(
                _action_url(server.id),
                json={'os-start': None})
            if wait:
                _wait(timeout, cloud, server, action, module, sdk)
                module.exit_json(changed=True)
        if action == 'pause':
            if not _system_state_change(action, status):
                module.exit_json(changed=False)
            cloud.compute.post(