docs: remove code in universal hero detail component (#25215)

This reverts commit e9cc3dad8f39bc8dfabfb708a825f90fcd2ab697.

PR Close #25215

aio/content/examples/universal/src/app/hero-detail/hero-detail.component.ts

@@ -1,4 +1,4 @@
-import { Component, OnInit, Input } from '@angular/core';
+import { Component, OnInit } from '@angular/core';
 import { ActivatedRoute } from '@angular/router';
 import { Location } from '@angular/common';
 
@@ -11,7 +11,7 @@ import { HeroService }  from '../hero.service';
   styleUrls: [ './hero-detail.component.css' ]
 })
 export class HeroDetailComponent implements OnInit {
-  @Input() hero: Hero;
+  hero: Hero;
 
   constructor(
     private route: ActivatedRoute,