docs: fix lazy loading example dir name (#21475)

PR Close #21475

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

@@ -0,0 +1,22 @@
+import { BrowserModule } from '@angular/platform-browser';
+import { NgModule } from '@angular/core';
+import { FormsModule } from '@angular/forms';
+import { HttpModule } from '@angular/http';
+import { AppRoutingModule } from './app-routing.module';
+
+import { AppComponent } from './app.component';
+
+@NgModule({
+  declarations: [
+    AppComponent
+  ],
+  imports: [
+    BrowserModule,
+    FormsModule,
+    HttpModule,
+    AppRoutingModule
+  ],
+  providers: [],
+  bootstrap: [AppComponent]
+})
+export class AppModule { }