Allow for custom polling intervals when deploying ARM templates

[johndowns]

Is your feature request related to a problem? Please describe. Currently customers who spend a lot of time developing, testing, and debugging ARM templates using the Azure CLI have to wait until the system decides to poll for updates, which might be up to ~30 seconds after the deployment completes. This small delay adds up and is quite frustrating.

Describe the solution you'd like Please consider adding the ability to specify the status polling interval when deploying ARM templates using az group deployment create, az deployment create, New-AzResourceGroupDeployment, and New-AzDeployment.

Additional context When deploying ARM templates using the Azure CLI and PowerShell, there is currently no way to specify how frequently the deployment should be polled for updates. There is built-in behaviour that does a semi-exponential backoff, which is a reasonable default behaviour - but in some circumstances (e.g. when deploying and debugging templates interactively) it is preferable to poll for status updates and completion more frequently to avoid wasting time waiting for a polling interval to complete.

[yonzhan]

ARM

[zhoxing-ms]

This PR can only be supported after the ARM service optimizes the overall throttling logic, so it is temporarily marked as Do Not Merge. @marcre If there is any optimization on the service side in the feture, please inform us in time