docs(di): fix broken link to ngmodules faq (#3252)

Author: juristr

public/docs/ts/latest/guide/dependency-injection.jade

@@ -289,7 +289,7 @@ block ngmodule-vs-component
 
   .l-sub-section
     :marked
-     Also see *"Should I add app-wide providers to the root `AppModule` or the root `AppComponent`?"* in the [NgModule FAQ](../cookbook/ngmodule-faq.html#root-component-or-module).
+     Also see *"Should I add app-wide providers to the root `AppModule` or the root `AppComponent`?"* in the [NgModule FAQ](../cookbook/ngmodule-faq.html#q-root-component-or-module).
 
 :marked
   ### Preparing the HeroListComponent for injection