Configure/Deploy PurgeEventRecordsJob

The purge events job is not currently being deployed to any of our environments. Configure the job in the swatch-metrics clowdapp.yaml so that is deployed and run based on the existing retention policy configuration.  All logic to do the purge exists today and is just not being run.

As part of this work, we should move to using a curl based job. Currently, the event purge logic is coupled to the snapshot retention controller. Move this to the swatch-metrics service since this is where events are getting created.

DONE:

• Internal API endpoint in swatch-metrics service is created that will be used to trigger the cleanup.
• Job configured in the  swatch-metrics clowdapp.yaml that calls the above API when run.