Update Analyzer Test Infrastructure

[merriemcgaw]

.NET version

New Clipboard analyzers have additional requirements of the test infrastructure.

Did it work in .NET Framework?

Not tested/verified

Did it work in any of the earlier releases of .NET Core or .NET 5+?

No response

Issue description

A little bit more testing is needed.

Steps to reproduce

N/A

[KlausLoeffelmann]

Due to recent events, we need to move this to Preview 6+.