Add missing run_upgrade

synapse/storage/schema/delta/31/search_update.py

@@ -63,3 +63,7 @@ def run_create(cur, database_engine, *args, **kwargs):
         sql = database_engine.convert_param_style(sql)
 
         cur.execute(sql, ("event_search_order", progress_json))
+
+
+def run_upgrade(cur, database_engine, *args, **kwargs):
+    pass