cleanup

Author: chenyukang

compiler/rustc_borrowck/src/diagnostics/mutability_errors.rs

@@ -1341,7 +1341,7 @@ impl<'infcx, 'tcx> MirBorrowckCtxt<'_, '_, 'infcx, 'tcx> {
                     };
                     err.span_suggestion_verbose(
                         span,
-                        format!("consider {changing} this binding's type xxx"),
+                        format!("consider {changing} this binding's type"),
                         sugg,
                         Applicability::HasPlaceholders,
                     );