Implementation outline

• create a new TTL engine configuration property for task metric
• adjust history cleanup task to also delete the task metrics based on the timestamp column and the defined TTL (removal time-based and end time-based)
• add the delete methods to the metrics REST endpoint at DELETE /metrics/task-worker with an optional date (data prior to that date will be deleted or all data will be deleted when no date is provided)
  • should be only allowed for camunda-admin
  • should write user operation log
  • add documentation (docs-manual and OpenAPI)