Rename filename

Author: JohnTitor

src/tools/tidy/src/errors.rs

@@ -15,7 +15,7 @@ pub fn check(path: &Path, bad: &mut bool) {
                 &mut |path| super::filter_dirs(path) || path.ends_with("src/test"),
                 &mut |file| {
         let filename = file.file_name().unwrap().to_string_lossy();
-        if filename != "diagnostics.rs" && filename != "diagnostic_list.rs" {
+        if filename != "error_codes.rs" && filename != "diagnostic_list.rs" {
             return
         }