docs: update contributing page (angular#26497)

PR Close angular#26497

aio/content/marketing/contribute.html

@@ -17,6 +17,17 @@ <h3 class="no-anchor">Angular</h3>
     <a href="https://github.com/angular/angular/blob/master/CONTRIBUTING.md" class="button button-blue" md-button>Contribute</a>
   </div>
 
+  <div class="card-section">
+    <div>
+      <h3 class="no-anchor">Angular CLI</h3>
+
+      Angular CLI makes it easy to create an application that already works, right out of the box. It already follows our best practices.
+
+    </div>
+
+    <a href="https://github.com/angular/angular-cli/blob/master/CONTRIBUTING.md" class="button button-blue" md-button>Contribute</a>
+  </div>
+
   <div class="card-section">
     <div>
       <h3 class="no-anchor">Angular Material</h3>
@@ -37,7 +48,7 @@ <h3 class="no-anchor">AngularFire</h3>
       to build your Angular app.
 
     </div>
-    <a href="https://github.com/angular/angularfire2" class="button button-blue" md-button> Contribute</a>
+    <a href="https://github.com/angular/angularfire2/blob/master/CONTRIBUTING.md" class="button button-blue" md-button> Contribute</a>
   </div>
 
 </article>