Create launch checklist for data pipeline deployments (etl, gardener, schemas)

[stephen-soltesz]

The post mortem action items from the 2022-03-18 Incident: Deploying ndt5 extended views included creating a launch checklist to support the process of making intricate changes with unexpected effects. For example:

• Documented steps
• Public communication: announce, deploy, announce.
• Value-based comparisons.
• Validate counts with end to end queries using views (before and after deployments).
• Second reviewer of data prior to deployment (if changing behavior (vs adding))