message: .mci.yml: Temporarily fall back from 'latest' clusters to 3.4
  This works around a mongo-orchestration issue
  (https://github.com/10gen/mongo-orchestration/pull/229), which will be
  addressed in a newer version of mongo-orchestration.
  This temporary fallback change to .mci.yml will be reverted in
diff: variables:
  mongodb_version:
  - version_latest: &version_latest latest
  + # TODO CXX-1037: Define "version_latest" to "latest", not "3.4".
  + version_latest: &version_latest 3.4
  version_32: &version_32 3.2
  ## Use newer compiler path variables
  