Also fix `Permutation_cons`.

2 jobs for !291 with robbert/Permutation_app in 4 minutes and 58 seconds (queued for 5 seconds)
latest detached
Status Name Job ID Coverage
  Build
passed build-coq.8.10.2 #133290
fp

00:04:57

passed build-coq.8.13.2-mr #133289
fp

00:04:30