[extensions-web/deploy] (14 commits) ...Merge branch 'master' into deploy

[Yuri Konotopov <ykonotopov src gnome org>]

Summary of changes:

  5deaff8... Add CI jobs for building and pushing Docker image to Quay (*)
  38132d4... ci: Add job for pushing frontend image to Quay (*)
  90c882a... ci: Switch frontend to fully qualified base image (*)
  3132bf5... users: migrate to custom User class (*)
  32aff8f... */*: a bit more formatting (*)
  f941470... openshift: return single PYTHON_VERSION arg (*)
  706c4aa... openshift: switch to default nginx image (*)
  b56a6f2... openshift: drop nginx Dockerfile (*)
  8ece7d7... openshift: Dockerfile: move PYTHONUNBUFFERED to proper stag (*)
  6fc16d7... openshift: dockerfile: drop XAPIAN_VERSION default value (*)
  5338c5b... ci: rename test stage to `build and test` (*)
  54d30ac... ci: pin pipeline to MRs and protected branches only (*)
  82761dd... ci: pin deploy job to `deploy` branch and drop manual restr (*)
  f77b4f9... Merge branch 'master' into deploy

(*) This commit already existed in another branch; no separate mail sent