[migrations] fix pg empty query error

Author: iam047801

migrations/pgmigrations/20240507095608_code_data_kv_storage.up.sql

@@ -1,2 +1,4 @@
--- UPDATE account_states SET code = NULL;
--- UPDATE account_states SET data = NULL;
+BEGIN;
+    -- UPDATE account_states SET code = NULL;
+    -- UPDATE account_states SET data = NULL;
+COMMIT;