docs(tutorial/step-9): link to list of filters rather than filterProvider

Closes #8082

Author: wcn3

docs/content/tutorial/step_09.ngdoc

@@ -120,7 +120,7 @@ You should now see the following output in the Karma tab:
 
 # Experiments
 
-* Let's experiment with some of the {@link ng.$filterProvider built-in Angular filters} and add the
+* Let's experiment with some of the {@link api/ng/filter built-in Angular filters} and add the
 following bindings to `index.html`:
   * `{{ "lower cap string" | uppercase }}`
   * `{{ {foo: "bar", baz: 23} | json }}`