style(docs-infra): clean up Tour-of-Heroes examples (#36483)

I noticed these minor styling issues while aligning the `universal`
examples with the `toh-pt6` example (in a subsequent commit).

PR Close #36483

aio/content/examples/toh-pt5/src/app/hero-detail/hero-detail.component.css

@@ -19,7 +19,6 @@ button {
   padding: 5px 10px;
   border-radius: 4px;
   cursor: pointer;
-  cursor: hand;
 }
 button:hover {
   background-color: #cfd8dc;

aio/content/examples/toh-pt6/src/app/app.module.ts

@@ -59,6 +59,5 @@ import { MessagesComponent }    from './messages/messages.component';
 // #docregion import-httpclientmodule
 })
 // #enddocregion import-httpclientmodule
-
 export class AppModule { }
 // #enddocregion , v1

aio/content/examples/toh-pt6/src/app/hero-detail/hero-detail.component.css

@@ -18,7 +18,7 @@ button {
   border: none;
   padding: 5px 10px;
   border-radius: 4px;
-  cursor: pointer; cursor: hand;
+  cursor: pointer;
 }
 button:hover {
   background-color: #cfd8dc;

aio/content/examples/toh-pt6/src/app/in-memory-data.service.ts

@@ -1,7 +1,7 @@
 // #docregion , init
+import { Injectable } from '@angular/core';
 import { InMemoryDbService } from 'angular-in-memory-web-api';
 import { Hero } from './hero';
-import { Injectable } from '@angular/core';
 
 @Injectable({
   providedIn: 'root',