As discussed in PR#5421, capturing `@error` is inconsistent, requiring
deep nesting (or priority) in order to correctly have red backgrounds to
it.
Some queries has this capture, some don't. For consistency purposes,
removing all of them is more preferable.
For re-enabling error, either add `(ERROR) @error` or `(ERROR _ @error)`
to your custom queries.
* Update parsers: ocamllex
Update its highlight to make it compatible with the new parser
* highlights(ocamllex): follow newest changes from upstream
The upstream grammar added highlights in the latest version, change our
highlight so they reflect better the intention of the grammar's author