[JamBalaya56562]

Closes: #4461.

Supersedes #4461 by @aoright, which has been waiting on the Google CLA since August. This is the same change on current master; thanks to @aoright for the original fix.

• In github/github.go, correct on-premise to on-premises in the media types preview comment.
• Add the missing trailing periods to two Client struct field comments.

Verified locally: gofmt, go build ./..., go vet ./github/, and custom-gcl 0 issues.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 98.62%. Comparing base (28d2616) to head (fe6fd59).

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #4652   +/-   ##
=======================================
  Coverage   98.62%   98.62%           
=======================================
  Files         201      201           
  Lines       18811    18811           
=======================================
  Hits        18553    18553           
  Misses        258      258           

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[gmlewis]

Thank you, @JamBalaya56562 , and for the nice comments and generous offer. I'm hoping we can move forward with your offer.

Since you may be the new maintainer soon, if you change "Superseeds" to "Closes" in the PR's description, then GitHub will automatically close that PR when this one merges. 😁

[gmlewis]

LGTM.
Merging.