CI docs: delete stale files

6 jobs for master in 7 minutes and 58 seconds (queued for 1 minute and 46 seconds)
Status Name Job ID Coverage
  Build
passed build-coq.8.6.1 #7730
fp-timing

00:02:09

passed build-coq.8.7.1 #7729
fp-timing

00:02:11

 
  Deploy
passed opam #7731

00:00:16

 
  Build More
passed build-coq.8.6.0 #7734
fp-timing

00:02:11

passed build-coq.8.7.0 #7733
fp-timing

00:02:07

passed build-coq.8.7.dev #7732
fp-timing

00:02:27