Fixed typo in docs/intro/tutorial07.txt

docs/intro/tutorial07.txt

@@ -3,7 +3,7 @@ Writing your first Django app, part 7
 =====================================
 
 This tutorial begins where :doc:`Tutorial 6 </intro/tutorial06>` left off. We're
-continuing the Web-poll application and will focus on customizing the Django's
+continuing the Web-poll application and will focus on customizing Django's
 automatically-generated admin site that we first explored in :doc:`Tutorial 2
 </intro/tutorial02>`.