scheduled-query extension does not skip validation

### Related command
```
az monitor scheduled-query create
```
### Extension name (the extension in question)
scheduled-query

### Description of issue
When running the following command on a newly created keyvault:

```
QUERY='AzureDiagnostics | where clientInfo_s !contains "Go/go" | where OperationName == "SecretSet" or OperationName == "SecretGet" or OperationName == "SecretUpdate" or OperationName == "SecretDelete" or OperationName == "SecretPurge" | mv-expand parse_json(AdditionalFields) | extend User=AdditionalFields["identity_claim_unique_name"] | where User != "" | project TimeGenerated, User, OperationName, requestUri_s | sort by TimeGenerated desc'

az monitor scheduled-query create \
--name "Keyvault Access - ${keyvault_name}" \
--resource-group ${keyvault_resource_group} \
--scopes ${SQ_SCOPE} \
--description "Keyvault Access - ${keyvault_name}" \
--evaluation-frequency 1h \
--window-size 1h \
--severity 3 \
--skip-query-validation true \
--target-resource-type Microsoft.KeyVault/vaults \
--condition "count 'QRY1' > 0" \
--condition-query QRY1="${QUERY}"
```

I get the error:
'mvexpand' operator: Failed to resolve scalar expression named 'AdditionalFields'

Which is logical normally when the keyvault was just created. However, I have used the --skip-query-validation true flag, and it looks like the query is still getting validated.

It should completely skip validation and implement the alert rule.