cubicweb-vcsfile #5704344 VCSRepo.head may raise CommandError [validation pending]

for instance if you call it by specifying both a path and a branch while the path doesn't exist in the branch

prioritynormal
typebug
done in2.1.0
load left0.000
closed by#9b2423c85483 VCSRepo.head() should raise CommandError but return None
patchVCSRepo.head() should raise CommandError but return None [applied]