ci: Run pkgcheck --commits in MR instead of full pkgcheck

Signed-off-by: Adrian 'nex' Schollmeyer <adrian.schollmeyer@fem.tu-ilmenau.de>
3 jobs for !32 with gitlab-ci in 9 minutes and 6 seconds (queued for 8 seconds)
detached
Status Name Job ID Coverage
  Repoman
passed repoman #431

00:05:36

 
  Lint
passed overlint #432

00:01:23

failed pkgcheck_commits #433

00:03:29

 
Name Stage Failure
failed
pkgcheck_commits Lint


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$ pkgcheck scan --exit --commits origin/master..HEAD
pkgcheck scan: error: [Errno 2] No such file or directory: 'git'
Cleaning up project directory and file based variables
ERROR: Job failed: exit code 1