Add HACKING.md

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6 jobs for hacking in 5 minutes and 40 seconds (queued for 1 second)
Status Job ID Name Coverage
  Lint
passed #676637
api-visibility

00:00:40

 
  Build
passed #676638
flatpak
flatpak:demo

00:01:58

passed #676639
reference

00:01:16

 
  Test
passed #676640
flatpak
flatpak:tests

00:02:27

 
  Review
passed #676641
review

00:00:33

failed #676642
allowed to fail manual
stop_review

 
Name Stage Failure
failed
stop_review Review There has been a missing dependency failure
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