docs: fix typo in dependency injection guide (angular#27616)

~~`HeroService` must provided in some parent injector~~
*`HeroService` must be provided in some parent injector*

PR Close angular#27616

aio/content/guide/dependency-injection.md

@@ -162,7 +162,7 @@ Here's the revised component, making use of the injected service, side-by-side w
   </code-pane>
 </code-tabs>
 
-`HeroService` must provided in some parent injector. The code in `HeroListComponent` doesn't depend on where `HeroService` comes from.
+`HeroService` must be provided in some parent injector. The code in `HeroListComponent` doesn't depend on where `HeroService` comes from.
 If you decided to provide `HeroService` in `AppModule`, `HeroListComponent` wouldn't change.
 
 {@a singleton-services}