fix: reach the log-retention job into _supabase over dblink

the supabase image pins cron.database_name to postgres, so pg_cron refuses
jobs scheduled from _supabase, where the log tables live; 1.3.2's upgrade
failed on the first live run with 'can only create extension in database
postgres'. The job now runs in postgres and deletes the _analytics
log_events_* rows in _supabase over a local dblink connection, which needs
no password because the image trusts local connections for supabase_admin.
version 1.3.3

tests/test_supaspin.py

@@ -134,11 +134,15 @@ class Values(unittest.TestCase):
     def test_log_retention_sql(self):
         # Logflare stores logs in _analytics.log_events_* and never deletes them; the job deletes
         # rows older than LOG_RETENTION and is scheduled under a fixed name so re-runs overwrite.
-        self.assertIn("schemaname = '_analytics'", sp.RETENTION_SQL)
-        self.assertIn("like 'log_events\\_%'", sp.RETENTION_SQL)
+        # pg_cron in the supabase image only runs jobs from the `postgres` database, so the job
+        # reaches the log tables in `_supabase` over a local dblink connection (trusted there).
+        self.assertIn("schemaname = ''_analytics''", sp.RETENTION_SQL)
+        self.assertIn("''log_events\\_%''", sp.RETENTION_SQL)
         self.assertIn(f"interval ''{sp.LOG_RETENTION}''", sp.RETENTION_SQL)
         self.assertIn(f"'{sp.LOG_RETENTION_JOB}'", sp.RETENTION_SQL)
         self.assertIn("cron.schedule", sp.RETENTION_SQL)
+        self.assertIn("dblink_connect", sp.RETENTION_SQL)
+        self.assertIn("user=supabase_admin", sp.RETENTION_SQL)
 
     def test_imgproxy_reads_the_storage_volume(self):
         img = self.v["persistence"]["imgproxy"]