[MIG] base_location: Avoid error on null zip numbers

base_location/migrations/12.0.1.0.0/post-migration.py

@@ -25,6 +25,7 @@ def migrate(env, version):
         FROM res_better_zip rbz
         WHERE city_id IS NULL
             AND rbz.country_id IS NOT NULL
+            AND rbz.name IS NOT NULL
         GROUP BY city, state_id, country_id
         ON CONFLICT DO NOTHING""",
     )