remove long-deprecated cofeT and dec_agree

4 jobs for ci/ralf/deprecated in 15 minutes and 46 seconds (queued for 2 seconds)
Status Job ID Name Coverage
  Build
passed #79698
fp
build-coq.8.10.2

00:08:10

passed #79697
fp-timing
build-coq.8.11.2

00:06:49

passed #79696
fp
build-coq.8.12.dev

00:15:46

passed #79699
fp
build-coq.8.9.1

00:07:44