Track replication started vs replication failed refs

Add metrics to track number of refs for which fetch operation have
started/completed/failed.

New metric names:
* plugins_pull_replication_fetch_refs_started_total
* plugins_pull_replication_fetch_refs_failed_total
* plugins_pull_replication_fetch_refs_completed_total

Bug: Issue 290254822
Change-Id: I20140b25064b034375ae6af19086bdff3717a770
3 files changed
tree: c581b93710150a5a95d45d246425583382007648
  1. example-setup/
  2. src/
  3. .gitignore
  4. BUILD
  5. Jenkinsfile
  6. LICENSE