Support for GitHub CLI

[koppor]

An alternative to asdf is aqua, which also runs on Windows. It offers support for installing the GitHub CLI.

I really like the idea of having the required command line tools ready. Instead of using winget and asking the users to update now and then, the tools can be updated "automatically" by a file versioned in the repository.

Since the GitHub CLI is very often required in a development setup (e.g., gh pr checkout xy), it would be nice if vfox would support that tool, too.