Add support for the pull request review thread event

[taisph]

Fixes #2324

[codecov]

Codecov Report

Merging #2326 (0f34008) into master (c28ccfd) will increase coverage by 0.00%.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##           master    #2326   +/-   ##
=======================================
  Coverage   98.04%   98.04%           
=======================================
  Files         117      118    +1     
  Lines       10454    10458    +4     
=======================================
+ Hits        10250    10254    +4     
  Misses        140      140           
  Partials       64       64           

Impacted Files	Coverage Δ
github/event_types.go	100.00% <ø> (ø)
github/messages.go	100.00% <ø> (ø)
github/event.go	100.00% <100.00%> (ø)
github/pulls_threads.go	100.00% <100.00%> (ø)

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[taisph]

I added the link https://docs.github.com/en/developers/webhooks-and-events/webhook-events-and-payloads#pull_request_review_thread which presumably will be the correct link once they update the docs by looking at the existing structure. I don't know what to expect with regards to when they'll update it as I managed to find a misnamed issue about the missing documentation that was created back in November 2021.

Should this PR be kept back until the docs are updated?

[gmlewis]

Should this PR be kept back until the docs are updated?

I don't think that's necessary. Many endpoints have been added in the past just based on observing the response received, so I think this is fine. It can always be updated once the official docs are released. Thank you, @taisph !

[gmlewis]

Thank you, @taisph !
LGTM.

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

[raynigon]

LGTM

[gmlewis]

Thank you, @raynigon !
Merging.