Dev: We can now use latest ocaml-lsp-server

We need to update the Opam repository tag to get the newest version. We do not use the opportunity to update our dependency tree, because we only care about ocamllsp.

Manually testing the MR

make build-dev-deps

Checklist

• Document the interface of any function added or modified (see the coding guidelines)
• Document any change to the user interface, including configuration parameters (see node configuration)
• Provide automatic testing (see the testing guide).
• For new features and bug fixes, add an item in the appropriate changelog (docs/protocols/alpha.rst for the protocol and the environment, CHANGES.rst at the root of the repository for everything else).
• Select suitable reviewers using the Reviewers field below.
• Select as Assignee the next person who should take action on that MR