docs: updated docs removed unnecessary imports and empty methods (angular#48513)

Removed empty methods and unnecessary imports in files

PR Close angular#48513

Author: Piyush132000

aio/content/examples/lazy-loading-ngmodules/src/app/orders/orders.component.ts

@@ -1,15 +1,8 @@
-import { Component, OnInit } from '@angular/core';
+import { Component } from '@angular/core';
 
 @Component({
   selector: 'app-orders',
   templateUrl: './orders.component.html',
   styleUrls: ['./orders.component.css']
 })
-export class OrdersComponent implements OnInit {
-
-  constructor() { }
-
-  ngOnInit() {
-  }
-
-}
+export class OrdersComponent {}

aio/content/examples/schematics-for-libraries/projects/my-lib/src/lib/my-lib.component.ts

@@ -1,4 +1,4 @@
-import { Component, OnInit } from '@angular/core';
+import { Component } from '@angular/core';
 
 @Component({
   selector: 'lib-my-lib',
@@ -9,11 +9,4 @@ import { Component, OnInit } from '@angular/core';
   `,
   styles: []
 })
-export class MyLibComponent implements OnInit {
-
-  constructor() { }
-
-  ngOnInit() {
-  }
-
-}
+export class MyLibComponent {}

aio/content/examples/styleguide/src/04-08/app/heroes/heroes.component.ts

@@ -1,11 +1,7 @@
-import { Component, OnInit } from '@angular/core';
+import { Component } from '@angular/core';
 
 @Component({
   selector: 'toh-heroes',
   templateUrl: './heroes.component.html'
 })
-export class HeroesComponent implements OnInit {
-  constructor() { /* ... */ }
-
-  ngOnInit() { /* ... */ }
-}
+export class HeroesComponent {}