* upstream/master: (195 commits)
  Fix expansion of discussions in diff
  Improve performance of MR show page
  Fix jumping between discussions on changes tab
  Update doorkeeper to 4.2.0
  Fix MR note discussion ID
  Handle legacy sort order values
  Refactor `find_for_git_client` and its related methods.
  Remove right margin on Jump button icon
  Fix bug causing “Jump to discussion” button not to show
  Small refactor and syntax fixes.
  Removed unnecessary service for user retrieval and improved API error message.
  Added documentation and CHANGELOG item
  Added checks for 2FA to the API `/sessions` endpoint and the Resource Owner Password Credentials flow.
  Fix behavior around commands with optional arguments
  Fix behavior of label_ids and add/remove_label_ids
  Remove unneeded aliases
  Do not expose projects on deployments
  Incorporate feedback
  Docs for API endpoints
  Expose project for environments
  ...