##### SUMMARY
`docker_container` should so some sanity checks that not two volumes / mount points use the same target inside the container, so that especially when recreating containers, they won't be destroyed first before recreating fails.

This becomes more important once #49808 is merged.

##### ISSUE TYPE
- Bug Report

##### COMPONENT NAME
docker_container

##### ANSIBLE VERSION
```
2.8.0
```

if mount_dict.get(option) is not None and datatype != req_datatype:
                    self.client.fail('{0} cannot be specified for mount "{1}" of type "{2}" (needs type "{3}")'.format(option, target, datatype, req_datatype))
            
            volume_driver = mount_dict.pop('volume_driver')
            volume_options = mount_dict.pop('volume_options')
            if volume_driver:
                if volume_options:
                    volume_options = clean_dict_booleans_for_docker_api(volume_options)
                mount_dict['driver_config'] = docker_types.DriverConfig(name=volume_driver, options=volume_options)
            if mount_dict['labels']:
                mount_dict['labels'] = clean_dict_booleans_for_docker_api(mount_dict['labels'])
            if mount_dict.get('tmpfs_size') is not None:
                try:
                    mount_dict['tmpfs_size'] = human_to_bytes(mount_dict['tmpfs_size'])
                except ValueError as exc:
                    self.fail('Failed to convert tmpfs_size of mount "{0}" to bytes: {1}'.format(target, exc))
            if mount_dict.get('tmpfs_mode') is not None:
                try:
                    mount_dict['tmpfs_mode'] = int(mount_dict['tmpfs_mode'], 8)
                except Exception as dummy:
                    self.client.fail('tmp_fs mode of mount "{0}" is not an octal string!'.format(target))
            
            mount_expected = dict(mount)
            mount_expected['tmpfs_size'] = mount_dict['tmpfs_size']
            mount_expected['tmpfs_mode'] = mount_dict['tmpfs_mode']
            
            mounts_list.append(docker_types.Mount(**mount_dict))
            mounts_expected.append(omit_none_from_dict(mount_expected))
        return mounts_list, mounts_expected
    def _process_rate_bps(self, option):