change color blindness resource link to fix #26

Author: aurooba

index.html

@@ -379,7 +379,7 @@ <h3>Get monthly tips to help you optimize your WordPress website</h3>
 					<li><a rel="noopener" target="_blank"
 							href="https://chrome.google.com/webstore/detail/high-contrast/djcfdncoelnlbldjfhinnjlhdjlikmph">High
 							Contrast add-on</a></li>
-					<li><a rel="noopener" target="_blank" href="http://www.checkmycolours.com/">Check my colours</a>
+					<li><a rel="noopener" target="_blank" href="https://www.toptal.com/designers/colorfilter">Colorblind Web Page Filter – helpful to see how your website appears for folks with colour blindness</a>
 					</li>
 				</ul>
 			</article>