Delete the vendered grammar/tree-sitter-mojo

I'm talking with the maintainer of https://github.com/lsh/tree-sitter-mojo
Now that mojo is 1.0, I think this should get published so packages such as this can use it.

You can also optionally delete it early, and I'll use a fork that carries it and make a far more minimal PR once it gets published.

Start by locating grammar/tree-sitter-mojo and searching the repository for references to the vendored grammar. The work is done when the vendored copy can be removed cleanly, or the issue is blocked until lsh/tree-sitter-mojo publishes the grammar; verify the remaining project checks afterward.

Scritto dal modello di indicizzazione a partire dal testo della issue.