[Buildkite] ES Snapshots Pipeline

[brianseeders]

ES Snapshots Pipeline

Create a pipeline for creating, testing, and promoting ES snapshots, based on the TeamCity implementation (since it's mostly node and easily portable).

The testing pipeline required for ES snapshots is essentially a subset of that required for tracked branches / PRs, so it's a good candidate to do first.

• ci.kibana.dev dashboard support for Buildkite or remove "Latest Verification" link for time being
• Build snapshot job
• Verify snapshot job
• Promote snapshot job
• Try c2-16 for ES build and see if it roughly doubles the speed
  • It doesn't
• Use depends_on for verify->promote trigger, so that post-build can always run
• Promote job is blocking asking for ES_SNAPSHOT_MANIFEST
• Add Input/Block step to Verify job for manual triggers
• Retries
• Migrate to current production bucket instead of ci-artifacts.kibana.dev test buckets
• Turn on daily schedule

[elasticmachine]

Pinging @elastic/kibana-operations (Team:Operations)