Update cookie.rst

We should reset the 'last_visit' item, because if it's not reset then every subsequent visit after one day will increment the 'visit' item.

chapters/cookie.rst

@@ -200,6 +200,7 @@ Now if you want to check if the cookie has been stored you can do so by accessin
 	        
 	        if (datetime.now() - datetime.strptime(last_visit_time[:-7], "%Y-%m-%d %H:%M:%S")).days > 0:
 	            request.session['visits'] = visits + 1
+	            request.session['last_visit'] = str(datetie.now())
 	    else:
 	        # The get returns None, and the session does not have a value for the last visit.
 	        request.session['last_visit'] = str(datetime.now())