Currently CMake is tested entirely through `build_linux_test.dart`. However, CMake is also used for Windows builds. This adds additional "generic" tests:

1. Parsing CMake files
2. Generating CMake config files.

In the future, this will be used to test that generated CMake config files contain the expected version information, which will be used to flow version information to Windows executables.

Part of https://github.com/flutter/flutter/issues/73652.