Adding missing field important to find branch in fork from same owner

[r-aramizu]

Hello there! I opened an issue to explain this suggestion.

I put the new field on your tests and keep working as before! There was a change that could solve my problem!

Fixes: #2872.

[gmlewis]

Thank you, @r-aramizu !
Please run go generate ./... in the top of the repo and then push (not force-push) the changes to this same PR, and that should fix the tests.
See CONTRIBUTING.md for more information.

[google-cla]

Thanks for your pull request! It looks like this may be your first contribution to a Google open source project. Before we can look at your pull request, you'll need to sign a Contributor License Agreement (CLA).

View this failed invocation of the CLA check for more information.

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[r-aramizu]

Thank you @gmlewis ! My bad for forget this 😅
Done!

[gmlewis]

@r-aramizu - please follow the CLA instructions from the comment above:
#2873 (comment)
in order to sign the Google CLA. Thank you!

[codecov]

Codecov Report

Merging #2873 (263a3f3) into master (352e4c8) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #2873   +/-   ##
=======================================
  Coverage   98.07%   98.07%           
=======================================
  Files         139      139           
  Lines       12357    12357           
=======================================
  Hits        12119    12119           
  Misses        162      162           
  Partials       76       76           

Files Changed	Coverage Δ
github/pulls.go	96.77% <ø> (ø)

[gmlewis]

Thank you, @r-aramizu !
LGTM.
Merging.

[r-aramizu]

Thank you @gmlewis to review it and help me with this! 🚀