fix(ocaml): use root_dir instead of root_markers for globs support (#6428)

## Description
As per
[comment](23b9cdeb34 (r165830889)),
use `root_dir` with `util.root_pattern` instead of `root_markers` for
globs support.

I don't actually do Ocaml to thoroughly test it, but it should work in
theory 😛
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## Related Issue(s)
None
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## Checklist

- [x] I've read the
[CONTRIBUTING](https://github.com/LazyVim/LazyVim/blob/main/CONTRIBUTING.md)
guidelines.

lua/lazyvim/plugins/extras/lang/ocaml.lua

@@ -26,15 +26,12 @@ return {
             "reason",
             "dune",
           },
-          root_markers = {
-            "*.opam",
-            "esy.json",
-            "package.json",
-            ".git",
-            "dune-project",
-            "dune-workspace",
-            "*.ml",
-          },
+          root_dir = function(bufnr, on_dir)
+            local util = require("lspconfig.util")
+            local fname = vim.api.nvim_buf_get_name(bufnr)
+            --stylua: ignore
+            on_dir(util.root_pattern("*.opam", "esy.json", "package.json", ".git", "dune-project", "dune-workspace", "*.ml")( fname))
+          end,
         },
       },
     },