Allow --useWinUI3 and --experimentalNugetDependency to be used together in CLI

[AgneLukoseviciute]

Summary

See #9099. Once WinAppSDK support is added in, we'll want to allow using these two flags simultaneously.

Motivation

Revert #5297 once it's no longer applicable.

[AgneLukoseviciute]

The latest version of the the CLI runs for all new projects, even against older RNW versions. Even if you can use both flags now for new projects, I don't think it will be true for older RNW versions.

yes actually @jonthysell has a good point - we would have to do a version check or something in the CLI to only allow certain versions. Really the CLI should delegate project creation logic to some version-specific package/code (we have an issue filed about syncing command line options)

Originally posted by @asklar in #9099 (comment)

[chrisglein]

One solution here may be that if you useWinUI3 that you only use the nuget (AKA we don't have the ability to build by source while also targeting WinUI3).

[jonthysell]

@AgneLukoseviciute Is this still something that makes sense for 0.69 or should it be moved to 0.70?

[rtorr]

Is this no longer relevant or is there still a plan for this?