Support line comments on PRs

[varmakarthik12]

#2832

[google-cla]

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[gmlewis]

Please run go generate ./... and push (not force-push) the changes to this PR.
See CONTRIBUTING.md for details.

[varmakarthik12]

Please run go generate ./... and push (not force-push) the changes to this PR. See CONTRIBUTING.md for details.

My Bad, This should be good now. LMK.

[codecov]

Codecov Report

Merging #2833 (c23b77d) into master (6c1dedd) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #2833   +/-   ##
=======================================
  Coverage   98.06%   98.06%           
=======================================
  Files         137      137           
  Lines       12289    12289           
=======================================
  Hits        12051    12051           
  Misses        162      162           
  Partials       76       76           

Impacted Files	Coverage Δ
github/pulls_comments.go	100.00% <ø> (ø)

[gmlewis]

Thank you, @varmakarthik12 !
LGTM.
Merging.