SDK ZIP does not include all AppHost packs

https://github.com/dotnet/sdk/pull/46911 has caused the removal of `arm64` and `x86` AppHost packs from `x64` version of SDK ZIP package.

This should be fixed as it is a regression. This is affecting builds in `deployment-tools` repo, see https://github.com/dotnet/deployment-tools/pull/437

The fix should include relevant tests to prevent future regressions.