Update link to match the block above

Author: Rachel Evans

html/lesson4/tutorial.md

@@ -180,7 +180,7 @@ Add an id `toolbar` to the outer `<div>`
 See what happens when you add a `target="_blank"` to your link
 
 ```html
-  <li> <a href="http://www.personal.psu.edu/djd5202/ass6.html" target="_blank">Computer Scientist</a></li>
+  <li> <a href="http://www.cs.yale.edu/homes/tap/Files/hopper-story.html" target="_blank">Computer Scientist</a></li>
 ```
 
 ### Styling the toolbar