Merge branch 'ralf/ci' into 'master'

update Makefile and CI

See merge request !2
2 jobs for master in 12 minutes and 22 seconds (queued for 3 seconds)
Status Job ID Name Coverage
  Build
passed #11963
fp
build-coq.8.6.1

00:12:22

passed #11962
fp
build-coq.8.7.2

00:11:35