Bump the OCaml compiler versions in the CI

[Halbaroth]

This commit introduces three changes:

• Bump 4.14.3 to 4.14.4 and 5.4.0 to 5.5.0,
• Use major version for the upper bound and minor version for the 4.14,
• Quote compiler versions as recommended by the documentation of setup-ocaml.

[bclement-ocp]

I'm OK with bumping the compiler versions that we use and with restricting to patch versions (i.e. 4.14 instead of 4.14.3), but I'm not sure I'm confident with the major 5 bound — if a new OCaml release accidentally breaks something, that would also brick our CI.

I think new OCaml releases are infrequent enough that we can keep 5.5 (I agree that patch releases are very likely fine) and bump manually it when there is a new minor release?

[Halbaroth]

The minimal version for js_of_ocaml 6.4.0 is OCaml 4.13. We could bump the minimal version to 4.13 or 4.14?

[bclement-ocp]

I'd be fine bumping the minimal version to 4.13 / 4.14 but then we need to do it in the opam files as well — otherwise we risk accidentally using APIs that are not available on older OCaml versions. (I think if we bump the minimal version it should be 4.13 as that is what is still in debian oldstable)

Although do we really need to test the js_of_ocaml build on all versions? I think it's fine to only test it on 4.14 (or even on 5.x).

[Halbaroth]

/home/runner/work/alt-ergo/alt-ergo/_build/default/src/bin/js/main_text_js.bc.js:16468
b ||= a.length - 1 < (ofs + len | 0) ? 1 : 0;
^^^

NOOOOOOOOOOOOOOOO... again a bug of jsoo?

[bclement-ocp]

/home/runner/work/alt-ergo/alt-ergo/_build/default/src/bin/js/main_text_js.bc.js:16468
b ||= a.length - 1 < (ofs + len | 0) ? 1 : 0;
^^^

NOOOOOOOOOOOOOOOO... again a bug of jsoo?

Apparently ||= is only supported since nodejs 15 (released in 2020) but we are still using an ancient nodejs 14 (?!) in the CI.