update Django for APIs book to 3.0 edition (#7164)

Author: wsvincent

docs/community/tutorials-and-resources.md

@@ -11,8 +11,8 @@ There are a wide range of resources available for learning and using Django REST
   <a class="book-cover" href="https://www.twoscoopspress.com/products/two-scoops-of-django-1-11">
     <img src="../../img/books/tsd-cover.png"/>
   </a>
-  <a class="book-cover" href="https://wsvincent.com/books/">
-    <img src="../../img/books/rad-cover.png"/>
+  <a class="book-cover" href="https://djangoforapis.com">
+    <img src="../../img/books/dfa-cover.jpg"/>
   </a>
   <a class="book-cover" href="https://books.agiliq.com/projects/django-api-polls-tutorial/en/latest/">
     <img src="../../img/books/bda-cover.png"/>