##### SUMMARY
When using the `host-header` condition for a load balancer rule if there are multiple values for the host header ansible fails to apply the changes with broken json output.

##### ISSUE TYPE
- Bug Report

##### COMPONENT NAME
elbv2

##### ANSIBLE VERSION
```
ansible 2.10.0.dev0
  config file = None
  configured module search path = [u'/home/mjmayer/.ansible/plugins/modules', u'/usr/share/ansible/plugins/modules']
  ansible python module location = /home/mjmayer/repos/ansible/lib/ansible
  executable location = /home/mjmayer/repos/ansible/bin/ansible
  python version = 2.7.15+ (default, Oct  7 2019, 17:39:04) [GCC 7.4.0]

```

##### CONFIGURATION
```
```

##### OS / ENVIRONMENT
Mint 19.2 / Ubuntu 18.04

##### STEPS TO REPRODUCE

```yaml
  - name: add a rule that uses the host header condition to the listener
    elb_application_lb:
      name: "{{ alb_name }}"
      subnets: "{{ alb_subnets }}"
      security_groups: "{{ sec_group.group_id }}"
      state: present
      purge_rules: no
      listeners:
        - Protocol: HTTP
          Port: 80
          DefaultActions:
            - Type: forward
              TargetGroupName: "{{ tg_name }}"
          Rules:
            - Conditions:
                - Field: host-header
                  Values:
                    - 'local.mydomain.com'
              Priority: '3'
              Actions:
                - TargetGroupName: "{{ tg_name }}"
                  Type: forward
      <<: *aws_connection_info
    register: alb

  - assert:
      that:
        - alb.changed
        - alb.listeners[0].rules|length == 4

  - name: test replacing the rule that uses the host header condition with multiple host header conditions
    elb_application_lb:
      name: "{{ alb_name }}"
      subnets: "{{ alb_subnets }}"
      security_groups: "{{ sec_group.group_id }}"
      purge_rules: no
      state: present
      listeners:
        - Protocol: HTTP
          Port: 80
          DefaultActions:
            - Type: forward
              TargetGroupName: "{{ tg_name }}"
          Rules:
            - Conditions:
                - Field: host-header
                  Values:
                    - 'local.mydomain.com'
                    - 'alternate.mydomain.com'
              Priority: '3'
              Actions:
                - TargetGroupName: "{{ tg_name }}"
                  Type: forward
      <<: *aws_connection_info
    register: alb
```
##### EXPECTED RESULTS
The second application of `elb_application_lb` should succeed and add the second host-header.


##### ACTUAL RESULTS
Ansible prints invalid json to the screen with the following error.
```paste below
Module invocation had junk after the JSON data
```

for current_listener in self.current_listeners:
            current_listener_passed_to_module = False
            for new_listener in self.listeners[:]:
                new_listener['Port'] = int(new_listener['Port'])
                if current_listener['Port'] == new_listener['Port']:
                    current_listener_passed_to_module = True
                    
                    listeners_to_add.remove(new_listener)
                    modified_listener = self._compare_listener(current_listener, new_listener)
                    if modified_listener:
                        modified_listener['Port'] = current_listener['Port']
                        modified_listener['ListenerArn'] = current_listener['ListenerArn']
                        listeners_to_modify.append(modified_listener)
                    break
            
            if not current_listener_passed_to_module and self.purge_listeners:
                listeners_to_delete.append(current_listener['ListenerArn'])
        return listeners_to_add, listeners_to_modify, listeners_to_delete
    def _compare_listener(self, current_listener, new_listener):
        """
        Compare two listeners.
        :param current_listener:
        :param new_listener:
        :return:
        """
        modified_listener = {}
        
        if current_listener['Port'] != new_listener['Port']:
            modified_listener['Port'] = new_listener['Port']