use a fork of Frama-C in Docker

docker/Dockerfile

@@ -4,6 +4,7 @@ RUN sudo apt-get update &&\
     sudo apt-get install -y cvc4 z3
 
 RUN opam repository set-url default "https://opam.ocaml.org" &&\
+    opam repository add lustrec "https://gitlab.isae-supaero.fr/lustrec/opam-repository.git" &&\
     opam update &&\
     opam depext -i\
     dune.2.9.1 dune-site menhir zarith ppx_deriving_yojson ocamlgraph alt-ergo frama-c.24.0 re