Remove un-implemented test

This test isn't meaningful as a number of other tests would fail if
sub-components were rendered without the presence of an `annotation`

src/sidebar/components/test/Annotation-test.js

@@ -294,8 +294,6 @@ describe('Annotation', () => {
 
         assert.isFalse(toggle.exists());
       });
-
-      it('should not render other annotation sub-components');
     });
   });