Suggest mise as installation method

Would it make sense to suggest [mise](https://mise.jdx.dev/) alongside other tools in the [installation documentation](https://www.ruby-lang.org/en/documentation/installation/)?

> mise is a polyglot tool version manager. It replaces tools like asdf, nvm, pyenv, rbenv, etc.

Mise is the [default](https://github.com/basecamp/omakub/pull/36) tool in DHH's Omakub, replacing rbenv and nodenv.