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##### SUMMARY
<!--- Explain the problem briefly below -->

`python-gitlab` library release a new version [v1.13.0](https://github.com/python-gitlab/python-gitlab/releases/tag/v1.13.0). User/Password authentication as been removed completely causing all Ansible GitLab module to fail... 

##### ISSUE TYPE
- Bug Report

##### COMPONENT NAME
<!--- Write the short name of the module, plugin, task or feature below, use your best guess if unsure -->

gitlab_group
gitlab_deploy_key
gitlab_hook
gitlab_project
gitlab_project_variable
gitlab_runner
gitlab_user

##### ANSIBLE VERSION
<!--- Paste verbatim output from "ansible --version" between quotes -->
All versions

- python-gitlab python module
extends_documentation_fragment:
  - auth_basic
options:
  state:
    description:
      - Create or delete project variable.
      - Possible values are present and absent.
    default: present
    type: str
    choices: ["present", "absent"]
  api_token:
    description:
      - GitLab access token with API permissions.
    required: true
    type: str
  project:
    description:
      - The path and name of the project.
    required: true
    type: str
  purge:
    description:
      - When set to true, all variables which are not untouched in the task will be deleted.
    default: false
    type: bool
  vars:
    description:
      - A list of key value pairs.
    default: {}