update Coq in the docker image
Upgrade Coq to version 8.16.1 in the docker image
also fix url for cvc4 1.8 and set ocaml version for "bench" to 4.09, because required by Coq 8.16
GitLab upgrade completed. Current version is 18.7.4
https://about.gitlab.com/releases/2025/12/18/gitlab-18-7-released/
Upgrade Coq to version 8.16.1 in the docker image
also fix url for cvc4 1.8 and set ocaml version for "bench" to 4.09, because required by Coq 8.16