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.