Use failure rather than cancelled or timed_out conclusions

[jglick]

Working around community/community#10255 as suggested in jenkins-infra/helpdesk#2741 (comment). Untested. CC @timja @basil @dduportal @lemeurherve @MarkEWaite

[codecov]

Codecov Report

Merging #250 (f9d423e) into master (d93ac64) will increase coverage by 0.30%.
The diff coverage is n/a.

@@             Coverage Diff              @@
##             master     #250      +/-   ##
============================================
+ Coverage     80.49%   80.79%   +0.30%     
  Complexity      170      170              
============================================
  Files            16       16              
  Lines           528      526       -2     
  Branches         49       49              
============================================
  Hits            425      425              
+ Misses           81       79       -2     
  Partials         22       22              

Impacted Files	Coverage Δ
...ins/plugins/checks/github/GitHubChecksDetails.java	78.02% <ø> (+1.67%)	⬆️

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[basil]

Sounds right, but I have no familiarity with this plugin.

[jglick]

I do not have much either, except to the extent that I wrote a similar plugin for CloudBees CI.