Add warning message when deleting amlarc extension

src/k8s-extension/azext_k8s_extension/partner_extensions/AzureMLKubernetes.py

@@ -163,7 +163,10 @@ def Update(self, extension, auto_upgrade_minor_version, release_train, version):
         )
 
     def Delete(self, client, resource_group_name, cluster_name, name, cluster_type):
-        pass
+        # Give a warning message
+        logger.warning("If nvidia.com/gpu or fuse resource is not recognized by kubernetes after this deletion, "
+                       "you probably have installed nvidia-device-plugin or fuse-device-plugin before installing AMLArc extension. "
+                       "Please try to reinstall device plugins to fix this issue.")
 
     def __validate_config(self, configuration_settings, configuration_protected_settings):
         # perform basic validation of the input config