Ensure we test on TFMs that have unique RID-specific assets

[ericstj]

We were missing cases where the RID-specific asset had a different framework than RID agnostic. As a result we wouldn't test all TFMs that had different assets.

https://github.com/dotnet/runtime/blob/d40dc6eb1398f25d083a818436c54810917e2147/src/libraries/System.Speech/src/System.Speech.csproj#L4
https://github.com/dotnet/runtime/blob/d40dc6eb1398f25d083a818436c54810917e2147/src/libraries/System.Diagnostics.EventLog/src/System.Diagnostics.EventLog.csproj#L4

[ViktorHofer]

Nit: Isn't the rid part now dead code?

[ericstj]

RID part is not dead yet, not until I merge my PR. This is needed regardless because it makes sure we test frameworks that will have RID-specific runtime targets. I noticed that when testing my PR.

Once my PR is merged to runtime we can delete the RID part of this.

[ViktorHofer]

Works for me 👍

[Anipik]

i have a pr in pipeline which remodels everything, i can delete the rid as part of it.