Skip most of the Mozilla Social checks (#6438)

bqetl_project.yaml

@@ -293,6 +293,7 @@ generate:
     - sql/moz-fx-data-shared-prod/org_mozilla_reference_browser_derived/baseline_clients_last_seen_v1/checks.sql
     - sql/moz-fx-data-shared-prod/org_mozilla_ios_focus_derived/baseline_clients_last_seen_v1/metadata.yaml
     - sql/moz-fx-data-shared-prod/org_mozilla_ios_focus_derived/baseline_clients_last_seen_v1/bigconfig.yml
+    - sql/moz-fx-data-shared-prod/org_mozilla_social_nightly_derived/baseline_clients_last_seen_v1/checks.sql
     skip_apps:
     - mlhackweek_search
     - moso_mastodon_android

sql/moz-fx-data-shared-prod/org_mozilla_social_nightly_derived/baseline_clients_last_seen_v1/checks.sql

@@ -0,0 +1,5 @@
+-- Override the generated checks, as this application doesn't send a lot of data.
+-- Eventually this app will be shut down completely: https://mozilla-hub.atlassian.net/wiki/spaces/MozSocial/pages/313229496/Mozilla+Social+Shutdown
+
+#warn
+{{ is_unique(["client_id"], where="submission_date = @submission_date") }}