Add engagement

sql_generators/mobile_kpi_support_metrics/templates/engagement.metadata.yaml

@@ -8,6 +8,7 @@ owners:
 labels:
   schedule: daily
   incremental: true
+  shredder_mitigation: true
 scheduling:
   dag_name: bqetl_mobile_kpi_metrics
   depends_on_past: false

sql_generators/mobile_kpi_support_metrics/templates/engagement.schema.yaml

@@ -2,7 +2,7 @@ fields:
 - mode: NULLABLE
   name: submission_date
   type: DATE
-  description:
+  description: Submission Date
 
 - mode: NULLABLE
   name: first_seen_date