Continue removing MyError.

src/parser/babel_call.rs

@@ -216,9 +216,7 @@ fn impl_balanced_bracket<
         }
 
         if fail_parser(remaining).is_ok() {
-            return Err(nom::Err::Error(CustomError::MyError(MyError(
-                "Fail parser matched.",
-            ))));
+            return Err(nom::Err::Error(CustomError::Static("Fail parser matched.")));
         }
 
         let (remain, _) = anychar(remaining)?;