az aks update fails due to ERROR: (LinkedInvalidPropertyId) Property id '' at path 'properties.addonProfiles.omsagent.config.LogAnalyticsWorkspaceResourceID' is invalid.

### Describe the bug

Whenever `az aks update` runs, it fails with an error

`ERROR: (LinkedInvalidPropertyId) Property id '' at path 'properties.addonProfiles.omsagent.config.LogAnalyticsWorkspaceResourceID' is invalid. Expect fully qualified resource Id that start with '/subscriptions/{subscriptionId}' or '/providers/{resourceProviderNamespace}/'. Code: LinkedInvalidPropertyId Message: Property id '' at path 'properties.addonProfiles.omsagent.config.LogAnalyticsWorkspaceResourceID' is invalid. Expect fully qualified resource Id that start with '/subscriptions/{subscriptionId}' or '/providers/{resourceProviderNamespace}/'.
`

### Related command

az aks update

### Errors

ERROR: (LinkedInvalidPropertyId) Property id '' at path 'properties.addonProfiles.omsagent.config.LogAnalyticsWorkspaceResourceID' is invalid. Expect fully qualified resource Id that start with '/subscriptions/{subscriptionId}' or '/providers/{resourceProviderNamespace}/'. Code: LinkedInvalidPropertyId Message: Property id '' at path 'properties.addonProfiles.omsagent.config.LogAnalyticsWorkspaceResourceID' is invalid. Expect fully qualified resource Id that start with '/subscriptions/{subscriptionId}' or '/providers/{resourceProviderNamespace}/'.

### Issue script & Debug output

$ az aks show -n cluster-name -g rg-name

```
{
"aadProfile": null,
"addonProfiles": {
"omsagent": {
"config": {
"LogAnalyticsWorkspaceResourceID": "",
"useAADAuth": "true"
},
"enabled": false,
"identity": null
}
}
...
}
```

I don't know when exactly this started, but we were running same clusters for years already in the same configuration and this was never an issue. The monitoring addon was never enabled on these clusters. Now we have a bunch of clusters where update operation fails randomly.

### Expected behavior

Do not fail update configuration with disabled addon config.

### Environment Summary

"azure-cli": "2.61.0",

"azure-cli-core": "2.61.0",

"azure-cli-telemetry": "1.1.0",

"ai-examples": "0.2.5",

"aks-preview": "5.0.0b1",

"front-door": "1.0.17",

"ml": "2.26.1",

"resource-graph": "2.1.0",

"ssh": "2.0.3"

### Additional context

_No response_