message: fix manifest test
diff: @@ -33,7 +33,7 @@ suite('src/package-manifest', () => {
  const result = lookupDependencyMapping('polymer');
  assert.deepEqual(result, {
  npm: '@polymer/polymer',
  - semver: '3.0.0-pre.12',
  + semver: '^3.0.0-pre.13',
  });
  });
  });
  