when WAD installing the command succeed even though storageAccountSasToken is empty (in LAD, installation fail when storageAccountSasToken is empty)

Hi experts,

When az vm diagnostics set running, WAD installation will succeed even though storageAccountSasToken is empty. However, in LAD installation, it will fail.

"storageAccountSasToken is empty" mean like this:
set="{'storageAccountName':'$sa', 'storageAccountSasToken':''}"
extension=$(az vm diagnostics set --settings "$defcon" --protected-settings "$set" --subscription $subscription --resource-group $rg --vm-name $vm -o tsv --query name)

I think it should fail when storageAccountSasToken is empty because this value is essential. Please revise code not to install.

---
#### Document Details

⚠ *Do not edit this section. It is required for docs.microsoft.com ➟ GitHub issue linking.*

* ID: 7a9ab822-6524-9dd7-3bf4-1889e10d1266
* Version Independent ID: ec780873-d291-dda8-6b1d-c410e2d87b98
* Content: [az vm diagnostics](https://docs.microsoft.com/en-us/cli/azure/vm/diagnostics?view=azure-cli-latest)
* Content Source: [latest/docs-ref-autogen/vm/diagnostics.yml](https://github.com/MicrosoftDocs/azure-docs-cli/blob/main/latest/docs-ref-autogen/vm/diagnostics.yml)
* Service: **virtual-machines**
* GitHub Login: @rloutlaw
* Microsoft Alias: **routlaw**