feat: introduce detect-checked command, a quick check for whether a release has been requested

[bcoe]

breaking candidate-issue into two commands:

candidate-issue and detect-checked-issue;

This will allow us to run the less expensive (in terms of API calls) checkbox check more frequently as a cron, and the expensive candidate-issue which updates a candidate issue less frequently.

[codecov]

Codecov Report

Merging #93 into master will decrease coverage by 0.81%.
The diff coverage is 19.23%.

@@            Coverage Diff             @@
##           master      #93      +/-   ##
==========================================
- Coverage   47.18%   46.36%   -0.82%     
==========================================
  Files           9        9              
  Lines        1153     1182      +29     
  Branches       31       31              
==========================================
+ Hits          544      548       +4     
- Misses        607      632      +25     
  Partials        2        2

Impacted Files	Coverage Δ
src/candidate-issue.ts	36.5% <16.21%> (-4.2%)	⬇️
src/github.ts	22.68% <23.07%> (ø)	⬆️
src/release-pr.ts	37.71% <50%> (+0.35%)	⬆️

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update fe4cd4f...638da3b. Read the comment docs.