[Azure Mgmt Generator] Enables new resource detection logic for test project

[ArcturusZhang]

Now we have the resolveArmResources implemented, but no RP is using it.
As a starter, our test project should enable it first then we could try to use it on real RPs.

Current blockers of enabling it:

• [Bug]: SingletonResource is not properly resolved in resolveArmResources typespec-azure#3595
• [Azure Mgmt Generator] Support "specific extension" #54706