CTRT: Improve the OAuth 2.0 authentication identity provider documentation

Problem to solve

Implement a CTRT format and structure on the Configure GitLab as an OAuth 2.0 authentication identity provider documentation.

Further details

  • Implement a CTRT structure.
  • Bring content in line with style.

Proposal

  • Remove unnecessary or duplicated content.
  • Move Introduction to OAuth section to under H1.
  • Make language more active.
  • Address vale errors.

Who can address the issue

Technical writer.

Other links/references

technical-writing#702