Draft: Rz rdoc upgrade

Do not merge! (yet)

What does this MR do and why?

Updated rdoc gem and removes the patch

Changelog https://github.com/ruby/rdoc/releases

How to set up and validate locally

Numbered steps to set up and validate the change are strongly suggested.

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• I have evaluated the MR acceptance checklist for this MR.

Related to #419805

Related to https://gitlab.com/gitlab-org/gitlab/-/issues/351179