feat: add support for `markupgo` provider in contributors generator

[abdullah]

Resolves #66

Hi team 🙌

This PR introduces a new provider for the GitHub contributors generator. I have updated the documentation and generators/contributors.ts suggested as issue description.

Here’s a screenshot for a quick review of the documentation update.

[abdullah]

@pi0 I suggest to hide whitespace while reviewing. It is easy to understand what was changed for this PR 🙃

[abdullah]

@pi0 Did you have a chance to review this PR?

[abdullah]

@pi0 Hi, any update on this PR?

[pi0]

Sorry for late review. Any reason closed it @abdullah ?

[abdullah]

Ah, @pi0, it was completely closed by mistake. Sorry about that—I’ve re-opened it!

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 76.27119% with 14 lines in your changes missing coverage. Please review.

Please upload report for BASE (main@00334de). Learn more about missing BASE report.

Files with missing lines	Patch %	Lines
src/generators/contributors.ts	76.27%	14 Missing :warning:

Additional details and impacted files

@@           Coverage Diff           @@
##             main      #67   +/-   ##
=======================================
  Coverage        ?   75.23%           
=======================================
  Files           ?       17           
  Lines           ?     1046           
  Branches        ?      144           
=======================================
  Hits            ?      787           
  Misses          ?      258           
  Partials        ?        1           

:umbrella: View full report in Codecov by Sentry.
:loudspeaker: Have feedback on the report? Share it here.