Enable Catalyst Runtime Packs

[marek-safar]

Catalyst is a software-development tool that allows developers to write self-contained apps that can run on both macOS and iPadOS. To support that we need to build, test, and ship Catalyst runtime packs.

Work Items

• Introduce Catalyst RIDs Add new RID for Catalyst #47518
• Build Catalyst mono runtime packs for x64 and arm64 (like iOS)
  Produce coreclr based Catalyst runtime packs for x64 and arm64
• Run all libraries tests with Catalyst runtime packs
• Add functional/integration tests for Catalyst
• Ensure new runtime packs are trimmable

Oldest supported version: Mac Catalyst 13

[directhex]

A step is also needed for API review, as adding IsMacCatalyst() and IsMacCatalystVersionAtLeast() entries to src/libraries/System.Runtime/ref/System.Runtime.cs is subject to mandatory API change review.

[steveisok]

We're waiting on dotnet/xharness#435 in order to run tests.

[krwq]

@steveisok @directhex is this still planned for 6.0? Seems the other issue is fixed