Add support for Required Workflows

[claystation]

Fixes #2978
Suggestion to add support for Required Workflows in Github API.

[google-cla]

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[codecov]

Codecov Report

Merging #2979 (7057678) into master (630bfdb) will decrease coverage by 0.03%.
The diff coverage is 83.33%.

@@            Coverage Diff             @@
##           master    #2979      +/-   ##
==========================================
- Coverage   97.94%   97.92%   -0.03%     
==========================================
  Files         149      149              
  Lines       12836    12854      +18     
==========================================
+ Hits        12572    12587      +15     
- Misses        188      190       +2     
- Partials       76       77       +1     

Files	Coverage Δ
github/repos_rules.go	98.85% <83.33%> (-1.15%)	⬇️

[gmlewis]

Thank you, @claystation !
After a few tweaks, we should be ready for a second LGTM+Approval from any other contributor to this repo before merging.

[claystation]

Hey @gmlewis ! Thanks for the review :) I updated the code to reflect the correct suggestions!

[gmlewis]

It looks like some gofmt needs to be called, then we should be good to move forward on this PR.

[claystation]

Hey @gmlewis! I did a gofmt and generated files as requested in the check :) Should be good to go now!

[gmlewis]

Thank you, @claystation !
LGTM.

Awaiting second LGTM+Approval from any other contributor to this repo before merging.

[gmlewis]

Thank you, @valbeat !
Merging.