Add struct for workflow_job event

[ghost]

This is a new (as of now undocumented) event that has been darkshipped by GitHub.

It provides three actions: queued, started and completed, reusing the existing WorkflowJob struct.

Official documentation is supposedly soon to follow, but advance submission of this PR has been approved by GitHub staff.

You can hold up this PR until it drops. I will update it accordingly.

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[codecov]

Codecov Report

Merging #2038 (3de6833) into master (95b92df) will increase coverage by 0.00%.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##           master    #2038   +/-   ##
=======================================
  Coverage   97.87%   97.87%           
=======================================
  Files         107      107           
  Lines        6907     6909    +2     
=======================================
+ Hits         6760     6762    +2     
  Misses         81       81           
  Partials       66       66           

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)

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[gmlewis]

Thank you, @acuteaura !
Could you please also add this new event to ParsePayload and also a couple more places? If you search for WorkflowRunEvent then you should be able to find the other locations.

[gmlewis]

Excellent, thank you, @acuteaura !
LGTM.

Awaiting second LGTM before merging.

[Parker77]

LGTM.

[gmlewis]

Thank you, @Parker77 !
Merging.