Packaging games documention needs to be revised

[ThomasFOG]

The game packaging documentation needs to be revised: https://github.com/MonoGame/docs.monogame.github.io/blob/main/articles/getting_started/packaging_games.md

It assumes that AOT is the default distribution model of MonoGame apps, but this is not supported on all platforms. WindowsDX is incompatible with it (due to its dependency to WinForms, which is incompatible with trimming).

The documentation should be revised to remove the dependency to PublishAot, and the separate AOT note should mention that WindowsDX is incompatible.

[ThomasFOG]

The documentation should also mention how to use ContentTypeReaderManager.AddTypeCreator() if need be.