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##### SUMMARY
<!--- Explain the problem briefly below -->
The [docker_container](https://docs.ansible.com/ansible/latest/modules/docker_container_module.html) module recreates a container when the `restart_policy` is changed. This can be changed using the `docker update` command.

##### ISSUE TYPE
- Bug Report

##### COMPONENT NAME
[docker_container](https://docs.ansible.com/ansible/latest/modules/docker_container_module.html)

##### ANSIBLE VERSION
<!--- Paste verbatim output from "ansible --version" between quotes -->
```shell
$ ansible --version
ansible 2.9.2
  config file = /etc/ansible/ansible.cfg
  configured module search path = ['/home/ingmar/.ansible/plugins/modules', '/usr/share/ansible/plugins/modules']
  ansible python module location = /usr/lib/python3.7/site-packages/ansible
  executable location = /usr/bin/ansible
  python version = 3.7.5 (default, Oct 17 2019, 12:09:47) [GCC 9.2.1 20190827 (Red Hat 9.2.1-1)]
```

##### CONFIGURATION
<!--- Paste verbatim output from "ansible-config dump --only-changed" between quotes -->
```paste below
$ ansible-config dump --only-changed
<empty>
```

##### OS / ENVIRONMENT
<!--- Provide all relevant information below, e.g. target OS versions, network device firmware, etc. -->
```shell
$ lsb_release -a
LSB Version:    :core-4.1-amd64:core-4.1-noarch
Distributor ID: Fedora
Description:    Fedora release 30 (Thirty)
Release:        30
Codename:       Thirty
```

##### STEPS TO REPRODUCE
<!--- Describe exactly how to reproduce the problem, using a minimal test-case -->
1. Run the following playbook:
```sh
$ ansible-playbook docker-container-update.yml
```
<!--- Paste example playbooks or commands between quotes below -->
```yaml
- name: Container update restart_policy
  hosts: localhost
  tasks:
    - name: Container with restart_policy
      docker_container:
        name: restart_policy_example
        image: alpine
        state: present
        restart_policy: unless-stopped
        entrypoint: top
```
2. Change the `restart_policy` to `always` and run it again.
```sh
$ ansible-playbook docker-container-update.yml
```
<!--- Paste example playbooks or commands between quotes below -->
```yaml
- name: Container update restart_policy
  hosts: localhost
  tasks:
    - name: Container with restart_policy
      docker_container:
        name: restart_policy_example
        image: alpine
        state: present
        restart_policy: unless-stopped
        entrypoint: top
```
3. Notice by using the `docker ps` command that the container is recreated instead of updated.

##### EXPECTED RESULTS
I expect the container to be update with  the new `restart_policy` by using the docker update command:
```sh
$ docker update --restart=<new policy>
``` 

##### ACTUAL RESULTS
<!--- Describe what actually happened. If possible run with extra verbosity (-vvvv) -->
The container is recreated instead of updated.
I currently run a `command` task before the container which updates the command.
```yml
# Update docker restart policy
- name: Update docker container restart policy
  command: "docker update --restart={{ (restart_policy == false) | ternary('no', restart_policy) }} {{ container }}"
  ignore_errors: true
```
type: dict
    version_added: 2.4
  user:
    description:
      - Sets the username or UID used and optionally the groupname or GID for the specified command.
      - "Can be of the forms C(user), C(user:group), C(uid), C(uid:gid), C(user:gid) or C(uid:group)."
    type: str
  uts:
    description:
      - Set the UTS namespace mode for the container.
    type: str
  volumes:
    description:
      - List of volumes to mount within the container.
      - "Use docker CLI-style syntax: C(/host:/container[:mode])"
      - "Mount modes can be a comma-separated list of various modes such as C(ro), C(rw), C(consistent),
        C(delegated), C(cached), C(rprivate), C(private), C(rshared), C(shared), C(rslave), C(slave), and
        C(nocopy). Note that the docker daemon might not support all modes and combinations of such modes."
      - SELinux hosts can additionally use C(z) or C(Z) to use a shared or private label for the volume.
      - "Note that Ansible 2.7 and earlier only supported one mode, which had to be one of C(ro), C(rw),
        C(z), and C(Z)."
    type: list
    elements: str
  volume_driver:
    description:
      - The container volume driver.
    type: str
  volumes_from:
    description:
      - List of container names or IDs to get volumes from.