fix: normalize_chunk_name handles Windows paths with drive letter (#623)

Co-authored-by: ewing <[email protected]>

Author: piz-ewing

src/luau/require.rs

@@ -129,7 +129,7 @@ impl TextRequirer {
     }
 
     fn normalize_chunk_name(chunk_name: &str) -> &str {
-        if let Some((path, line)) = chunk_name.split_once(':') {
+        if let Some((path, line)) = chunk_name.rsplit_once(':') {
             if line.parse::<u32>().is_ok() {
                 return path;
             }