Also build examples in CI
I forgot that make check does not build the C examples which are our only way to test the C API. One has to try running make examples after having installed the software. This used to be checked in the Docker CI (and is thus still here in the Docker-based part of our CI) but I did not reproduce this behaviour in the newly introduced "APT-based" and "OPAM-based" CIs. This PR fixes that.
It is currently WIP as I suspect it might not work on Windows (we've had problems before). When the CI is fixed, I'll re-run the job and check that it indeed works on Windows (or fix it).
We are waiting for the links for Menhir & Visitors to be fixed:
- in the OPAM repository with https://github.com/ocaml/opam-repository/pull/18697 (fixed)
- in the OPAM repository for Windows with https://github.com/fdopen/opam-repository-mingw/pull/95 (fixed)
- in the OPAM repository of the Docker images with https://github.com/ocurrent/docker-base-images/issues/110 (fixed)
OK, CI is turning again but (as suspected) Windows is unhappy. I will look into it.
This PR is made irrelevant by all the changes in #136.