Build for target netstandard2.0 too in CI/CD

[o-l-a-v]

Summary of the new feature / enhancement

If netstandard2.0 is a wanted target framework for PSResourceGet there should be automated tests / builds against it so build does not break in the future:

• Target framework "netstandard2.0" does not build with error The name 'Registry' does not exist in the current context #1779

From what I can see it does not seem CI/CD build for netstandard2.0 currently:

• https://github.com/search?q=repo%3APowerShell%2FPSResourceGet+path%3A%2F%5E%28%5C.ci%5C%2F%7C%5C.github%5C%2F%29%2F++build.ps1&type=code

Proposed technical implementation details (optional)

No response