[FEATURE] Improve performance of policy as rules assignments exports

[BernieWhite]

Your suggestion

When an Azure environment has many policy assignments exporting policy assignments from a scope may take an extended unreasonable time to complete or not complete at all.

Additionally, the current implementation relies on Az.Resources and v7.x introduces breaking changes that affect the functionality of Export-AzPolicyAssignmentData. (#2970)

The intent is to rewrite export in C# using key components of the resource data export process that supports throttling, concurrency, and greatly improves performance over the PowerShell cmdlets.

Alternatives

na

Additional context

There is an incompatibility with PSRule v3 and Az.Resources modules. So this must be complete before PSRule v3 can be adopted.