Deprecation warning for GitHub login

[cyb3rko]

When building, the following deprecation warning is shown:

DeprecationWarning: Argument login_or_token is deprecated, please use auth=github.Auth.Token(...) instead
  File "/opt/homebrew/lib/python3.11/site-packages/mkdocs_git_committers_plugin/plugin.py", line 38, in on_config
    self.github = Github( base_url="https://" + self.config['enterprise_hostname'] + "/api/v3", login_or_token=self.config['token'] )
  File "/opt/homebrew/lib/python3.11/site-packages/github/MainClass.py", line 177, in __init__
    warnings.warn(