fix(@schematics/angular): update default app component message

Aligns the inline welcome message with the external template for consistency.

Author: alan-agius4

packages/schematics/angular/application/files/module-files/src/app/app__suffix__.ts.template

@@ -4,7 +4,8 @@ import { Component, signal } from '@angular/core';
   selector: '<%= selector %>',<% if(inlineTemplate) { %>
   template: `
     <h1>Hello, {{ title() }}</h1>
-
+    <p>Congratulations! Your app is running. 🎉</p>
+    
     <% if (routing) {
      %><router-outlet /><%
     } %>