Increase minimal version of Zarith

[Halbaroth]

We have to increase the minimal version of Zarith. Indeed, the function Q.of_string does not support decimal notation before Zarith > 1.11. See ocaml/Zarith#65

This issue cannot be detected by the opam repository CI as the command dune build @runtest-ci isn't running by this CI and the issue occurs only using both a switch with lower bounds and the frontend dolmen.

I run tests locally and it should work now.

To prevent such situations from recurring, I suggest to use the alias runtest to run all the tests and runtest-something to run locally quick tests.

As soon as opam 2.2 is stable, I will modify the CI in order to check lower bounds.

I also add ppxlib < 0.30.0 as a conflict instead of a dependency.

We have to backport this PR again...

[bclement-ocp]

Ah, indeed, good catch. Not sure I understand why this is not caught by dune build @runtest: this looks like a parsing issue and we should dune build @runtest should parse all the test files (we just don't run them with all the different solvers/options)?

[bclement-ocp]

Ah, indeed, good catch. Not sure I understand why this is not caught by dune build @runtest: this looks like a parsing issue and we should dune build @runtest should parse all the test files (we just don't run them with all the different solvers/options)?

Oh wait we generate tests with the runtest-quick target by default, not runtest. Yeah, the dolmen and legacy suites at least should be run on the runtest alias.