Enable 4.12.0 CI (#1275)
Enable 4.12.0 CI (#1275)


the-lambda-church/merlin,ocaml/merlin,rgrinberg/merlin,the-lambda-church/merlin,rgrinberg/merlin,dra27/merlin,ocaml/merlin,ocaml/merlin,the-lambda-church/merlin,dra27/merlin,rgrinberg/merlin,rgrinberg/merlin,dra27/merlin,ocaml/merlin,dra27/merlin