chore(helm): update model db version to 9 (#1074)

Because

- The model db version need to be updated.

This commit

- Updates model db version to 9.

charts/core/values.yaml

@@ -482,7 +482,7 @@ modelBackend:
   # -- The path of configuration file for model-backend
   configPath: /model-backend/config/config.yaml
   # -- The database migration version
-  dbVersion: 8
+  dbVersion: 9
   dbCloudVersion:
   instillCoreHost:
   # -- The configuration of Temporal Cloud