Merge branch 'stable-3.3'

* stable-3.3:
  Remove standalone build mode
  Remove unnecessary public qualifier from GetConfig.ConfigInfo
  Fix errorprone errors
  Define Provider<ProjectLevelConfig.Bare>, reduce code repetition
  Stop using deprecated JGit API getAllRefs
  Make compatible with Gerrit stable-3.3 branch
  Upgrade bazlets to latest stable-3.2 to build with API
  Upgrade bazlets to latest stable-3.1 to build with 3.1.10 API
  Bump Bazel version to 3.7.0
  Upgrade bazlets to latest stable-3.0 to build with 3.0.13 API
  Bump Bazel version to 3.5.0

Change-Id: Icc5a7f9f0e8b0a7d3af60c640e184f98947a3b86