Rename `gh` alias (git help) to `ghh`
Rename `gh` alias (git help) to `ghh`

This conflicts with several tools, including NodeGH [1] and
scm_breeze [2].

[1] https://github.com/robbyrussell/oh-my-zsh/issues/5313
[2] https://github.com/robbyrussell/oh-my-zsh/issues/5321

Related: #5130
tekniklr/oh-my-zsh,tekniklr/oh-my-zsh