Azure Firewall CLI needs to be updated to standard UX and made GA.

[yairt1974]

az feedback auto-generates most of the information requested below, as of CLI version 2.0.62

Describe the bug
Azure Firewall CLI - "the extension is in preview message” need to be removed. The product has been GA since 9/24/2018.

To Reproduce
az extension add -n azure-firewall

Expected behavior
no preview warning message.

[tjprescott]

The service being GA doesn't mean the commands are GA. That they still use the non-standard UX to silently create rulesets behind the scenes would keep the commands from being declared GA.

[tjprescott]

So the scope of this issue would need to be to update the extension to use the standard CLI UX, at which point it could be declared GA.

[yonzhan]

add to S171

[jsntcy]

@tjprescott, Could you please help explain That they still use the non-standard UX to silently create rulesets behind the scenes? and how can we update the extension to use the standard CLI UX?