[git] implement GIT_HASH using nix shellHook instead of the 'githash' hs package

4 jobs for dev-improve-api-version in 50 minutes and 46 seconds (queued for 19 minutes and 20 seconds)
latest
Status Job ID Name Coverage
  Cabal
passed #19148
cabal

00:25:44

 
  Stack
passed #19149
stack

00:02:47

 
  Bench
manual #19150
allowed to fail manual
bench
 
  Test
passed #19151
test

00:22:15