feat(footer): updated the signal url

Author: chrisramakers

views/shared/_dc_footer.ejs

@@ -3,7 +3,7 @@
   <span class="dc-footer--text">
     Put your R skills to the test
   </span>
-  <a class="dc-footer--link btn btn-primary" href="https://www.datacamp.com/signal">Start Now</a>
+  <a class="dc-footer--link btn btn-primary" href="https://assessment.datacamp.com/r-programming">Start Now</a>
   <span class="dc-footer--cross"><i class="fa fa-times" aria-hidden="true"></i></span>
 </div>
 <% }%>