docs(tutorial/step-4): fix e2e test

After a protractor update the test syntax had to be changed.

Closes angular#7919

Author: alexm

docs/content/tutorial/step_04.ngdoc

@@ -166,7 +166,7 @@ __`test/e2e/scenarios.js`:__
         "MOTOROLA XOOM\u2122"
       ]);
 
-      element(by.model('orderProp')).findElement(by.css('option[value="name"]')).click();
+      element(by.model('orderProp')).element(by.css('option[value="name"]')).click();
 
       expect(getNames()).toEqual([
         "MOTOROLA XOOM\u2122",