docs: remove service from region where it was added before it was created (#35354)

The message service was added in a section create message service but was impoted much before it removed those imports because they can be confusing

Fixes #35259

PR Close #35354

aio/content/examples/toh-pt4/src/app/heroes/heroes.component.1.ts

@@ -5,9 +5,9 @@ import { Observable } from 'rxjs';
 class DummyHeroesComponent {
 
   heroes: Observable<Hero[]>;
-
+  // #docregion ctor
   constructor(private heroService: HeroService) {}
-
+  // #enddocregion ctor
   // #docregion getHeroes
   getHeroes(): void {
     // #docregion get-heroes

aio/content/examples/toh-pt4/src/app/heroes/heroes.component.ts

@@ -5,8 +5,8 @@ import { Component, OnInit } from '@angular/core';
 import { Hero } from '../hero';
 // #docregion hero-service-import
 import { HeroService } from '../hero.service';
-import { MessageService } from '../message.service';
 // #enddocregion hero-service-import
+import { MessageService } from '../message.service';
 
 @Component({
   selector: 'app-heroes',