Use ridless PNSE configurations where applicable (#44230)

Use ridless PNSE configurations where applicable (#44230)

For projects that require platform support we should use a rid-less
configuration, i.e. $(NetCoreAppCurrent). That guarantees that PNSE
assemblies are available for new configurations that aren't represented
in the defined project's TargetFrameworks. This is especially important
for inbox assemblies.

I left the following assemblies as is as they are partial PNSEs:
- System.Security.Cryptography.Algorithms
- System.Net.NameResolution

System.Net.Requests and System.Net.WebClient are IL only but
intentionally marked as throwing on Browser.