message: docs: Change 'function' to 'method' for clarity that getHereos() is
  intended as a class method
  Change 'function' to 'method' for clarity that getHereos() is
  intended as a class method in Tour of Heroes part 4.
  PR Close
diff: @@ -139,7 +139,7 @@ sets the `heroService` parameter to the singleton instance of `HeroService`.
  ### Add `getHeroes()`
  -Create a function to retrieve the heroes from the service.
  +Create a method to retrieve the heroes from the service.
  <code-example path="toh-pt4/src/app/heroes/heroes.component.1.ts" header="src/app/heroes/heroes.component.ts" region="getHeroes">
  </code-example>
  