Add windows compilation support
Add basic support to compile why3 on Windows using the release of opam 2.2.0~beta3.
Edited by Basile Desloges
GitLab upgrade completed. Current version is 18.3.6
https://about.gitlab.com/releases/2025/07/17/gitlab-18-2-released/
https://about.gitlab.com/releases/2025/08/21/gitlab-18-3-released/
Add basic support to compile why3 on Windows using the release of opam 2.2.0~beta3.