Fix ansible_ssh_common_args in molecule.yml

[gardar]

Makes the option ansible_ssh_common_args in molecule.yml work as documented:

        driver:
          name: delegated
          options:
            managed: True
            ansible_connection_options:
              ansible_connection: ssh
              ansible_ssh_common_args: '-F /path/to/ssh-config'

Fixes: #2859
Fixes: #2931

[ssbarnea]

@gardar don't forget to fix the linter.

[gardar]

Missed this yesterday, thanks for fixing it for me @ssbarnea !