grammar: Don't require lower-case (helix-editor#4346)

Currently we always lower-case the grammar name when loading it. While it
is somewhat of an convention to name tree-sitter grammars in lowercase
there is no rule to enforce it.

This patch removes the lower-casing to allow all possible grammar names.

Signed-off-by: Christian Speich <cspeich@emlix.com>

helix-loader/src/grammar.rs

@@ -67,7 +67,6 @@ pub fn get_language(name: &str) -> Result<Language> {
 #[cfg(not(target_arch = "wasm32"))]
 pub fn get_language(name: &str) -> Result<Language> {
     use libloading::{Library, Symbol};
-    let name = name.to_ascii_lowercase();
     let mut library_path = crate::runtime_dir().join("grammars").join(&name);
     library_path.set_extension(DYLIB_EXTENSION);