Change string used to annotate static type issues to 'static type warning' in multitest

tests/language/src/FBoundedQuantificationTest.dart

 // Copyright (c) 2011, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 // Test for F-Bounded Quantification.
 
 class FBound<F extends FBound<F>> {}
 
 class Bar extends FBound<Bar> {}
 
 class SubBar extends Bar {}
 
 main() {
   FBound<Bar> fb = new FBound<Bar>();
-  FBound<SubBar> fsb = new FBound<SubBar>();  /// 01: static type error
+  FBound<SubBar> fsb = new FBound<SubBar>();  /// 01: static type warning
 }