remove the file

Author: genlin

support/azure/azure-kubernetes/create-upgrade-delete/subnet-with-external-resources-cannot-be-used-by-other-resources.md

@@ -39,8 +39,6 @@
       href: create-upgrade-delete/error-code-subscriptionrequeststhrottled.md
     - name: Throttled error (429)
       href: create-upgrade-delete/error-code-aksrequeststhrottled.md
-    - name: SubnetWithExternalResourcesCannotBeUsedByOtherResources error
-      href: create-upgrade-delete/subnet-with-external-resources-cannot-be-used-by-other-resources.md
     - name: Troubleshoot the AKSCapacityError error code
       href: create-upgrade-delete/akscapacityerror.md
     - name: VMExtensionProvisioningTimeout error