Merge branch 'stable-3.5' into stable-3.6

* stable-3.5:
  Increase FetchOne coverage with unit tests
  Display the in-flight taskId when a runway conflict is detected
  Restore the fetching of all refs with empty delta
  Allow to filter out refs from the fetch-replication deltas
  Do not accumulate replication events with retrying tasks
  Add replication taskId during the execution of the fetch
  Allow FetchOne to retry the failed ref only

Change-Id: Idf86be68b3678019a85e300e7174786bbd176b15