Update to Rust 1.73.0
What does this MR do and why?
https://gitlab.com/gitlab-org/ruby/gems/gitlab-glfm-markdown needs at least 1.70.0 - update to latest 1.73.0
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.