refac: on_valves_update hook added

main.py

@@ -268,18 +268,19 @@ async def update_valves(pipeline_id: str, form_data: dict):
 
     pipeline_module = PIPELINE_MODULES[pipeline_id]
 
-    await pipeline_module.on_shutdown()
     try:
         ValvesModel = pipeline_module.valves.__class__
         valves = ValvesModel(**form_data)
         pipeline_module.valves = valves
+
+        if hasattr(pipeline_module, "on_valves_update"):
+            await pipeline_module.on_valves_update()
     except Exception as e:
         print(e)
         raise HTTPException(
             status_code=status.HTTP_500_INTERNAL_SERVER_ERROR,
             detail=f"{str(e)}",
         )
-    await pipeline_module.on_startup()
 
     return pipeline_module.valves