CI docs: delete stale files

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

00:02:09

passed #7729
fp-timing
build-coq.8.7.1

00:02:11

 
  Deploy
passed #7731
opam

00:00:16

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

00:02:11

passed #7733
fp-timing
build-coq.8.7.0

00:02:07

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

00:02:27