Update explanation on @daiji256/rehype-mathml in plugins.md

[tats-u]

Initial checklist

• I read the support docs
• I read the contributing guide
• I agree to follow the code of conduct
• I searched issues and discussions and couldn’t find anything or linked relevant results below
• I made sure the docs are up to date
• I included tests (or that’s not needed)

Description of changes

The current explanation on @daiji256/rehype-mathml has the following problems:

• Readers can misunderstand the package name to be passed to npm i
• Readers who are searching a plugin for Temml cannot find it

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 100.00%. Comparing base (9bc5528) to head (77c8ab9).
Report is 25 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff            @@
##              main      #189   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files            6         6           
  Lines          154       163    +9     
=========================================
+ Hits           154       163    +9     

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[wooorm]

I am not sure about adding the scope name.

This list current goal is not to be a list of npm package names. It’s a list of plugin names.

[Daiji256]

Readers can misunderstand the package name to be passed to npm i

I decided to list it without a scope, consistent with other libraries such as @mapbox/rehype-prism, @benjc/rehype-scroll-to-top, and @hbsnow/rehype-sectionize.

[tats-u]

I forgot to revert addition of the namespace. Thank you for your notification.

[tats-u]

If other than Squash and Merge is going to be applied here, I will squash these 3 commits in one in advance. Please tell me so before merging or rebasing.

[wooorm]

I always squash! :) Thank you!

[tats-u]

Thank you for merging.