Please update wiki with at least tlmgr

[xaocon]

What did you expect to happen?

Find documentation about TeX Live package manager step and understand that it's called tlmgr in the config.

What actually happened?

Nothing in the wiki about it.

Additional Details

• Which operating system or Linux distribution are you using?
  N/A
• How did you install Topgrade?
  N/A
• Which version are you running?
  N/A

[xaocon]

I tried to find a way to fork this and add a PR but I don't think github supports it. Here's the line I added to my fork before I figured out you can't PR the wiki in case you want to use it in some way. If you really don't want to be updating the wiki yourself I'd be willing to take some time to try to update but I don't know how the permissions work.

* Upgrade [tlmgr](https://www.tug.org/texlive/tlmgr.html) TeX Live package manager