Merge branch 'master' into upgrade-to-webpack-v4

* master: (252 commits)
  Upgrade underscore.js
  Enable prometheus metrics by default
  Add signature verification badge to compare view
  Add Changelog
  Update instalation from source guide
  fix Web IDE file tree scroll issue
  Enable quick support actions default
  Backport of 4084-epics-username-autocomplete
  Remove top margin on the terms page with performance bar
  Backports every CE related change from ee-44542 to CE
  Fix typo in changelog entry
  fix missing space
  Backport IdentityLinker#failed? from GroupSaml callback flow
  Add ci_cd_settings delete_all dependency on project
  AutoDevOps Docs fix invalid external link
  Ignore knapsack and rspec_flaky
  Ensure web hook 'blocked URL' errors are stored in as web hook logs and properly surfaced to the user
  Partially revert ebcd5711 to fix runner pages
  Reuses `InternalRedirect` when possible
  Enforces terms in the web application
  ...