fix: use new molecule-plugins[docker]

[JonasPammer]

fixes a KeyError: 'docker' error i experienced on my devcontainer (both laptop and desktop) and which also happens in CI:

   File "/home/runner/work/cookiecutter-ansible-role/cookiecutter-ansible-role/ansible-role-myrole/.tox/py3-ansible-6/lib/python3.11/site-packages/molecule/api.py", line 30, in __getitem__
    return self.__dict__[i]
           ~~~~~~~~~~~~~^^^
KeyError: 'docker'
py3-ansible-6: exit 1 (0.84 seconds) /home/runner/work/cookiecutter-ansible-role/cookiecutter-ansible-role/ansible-role-myrole> molecule destroy pid=8844
  pre-commit: OK (5.13=setup[3.05]+cmd[2.08] seconds)
  py3-ansible-4: OK (208.70=setup[91.06]+cmd[0.74,17.08,2.63,97.19] seconds)
  py3-ansible-5: FAIL code 1 (103.82=setup[102.54]+cmd[0.42,0.85] seconds)
  py3-ansible-6: FAIL code 1 (34.50=setup[33.24]+cmd[0.42,0.84] seconds)

first kudo's go to robertdebock/ansible-role-bootstrap@d9a5f51 +
for completeness: a link to web archive showing mention of molecule-plugins in the official installation docs of molecule v5.0.0 as per ansible/molecule#3805

[JonasPammer]

no new warnings, CI now passes again, lgtm