Setting alert for Microsoft.ContainerRegistry/registries/privateEndpointConnections/writ

**Is your feature request related to a problem? Please describe.**

I have requested from customer to be able to set alert for the private endpoint approval activity from different AAD tenant.

Currently, we can see "Microsoft.ContainerRegistry/registries/privateEndpointConnections/write" in activity log, but "az monitor activity-log alert create" said it is not supported.



**Describe the solution you'd like**

possible to create alert against "Microsoft.ContainerRegistry/registries/privateEndpointConnections/write" like this.

```
az monitor activity-log alert create -n alerttest3 -g labprivateACR -a /subscriptions//resourcegroups/lab/providers/microsoft.insights/actiongroups/emailme --subscription -c category=Administrative and operationName=Microsoft.ContainerRegistry/registries/privateEndpointConnections/write and status=succeeded -s /subscriptions//resourceGroups/labprivateACR/providers/Microsoft.ContainerRegistry/registries/labacr20200528
```

**Describe alternatives you've considered**

**Additional context**

Currently, I can set the alert deleting operation name.

```
az monitor activity-log alert create -n acrpe -g labprivateacr -a /subscriptions/93b7ca88-d2cc-4381-97ec-f99f3a702495/resourcegroups/labprivateacr/providers/microsoft.insights/actiongroups/emailme --subscription -c category=Administrative and status=succeeded -s /subscriptions//resourceGroups/labprivateACR/providers/Microsoft.ContainerRegistry/registries/labacr20200519
```