Update reference link in Understanding of SC 2.4.2 (Page Titled) (#1025)

Fixes #825

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Co-authored-by: JAWS-test2 <>
Co-authored-by: Patrick H. Lauke <[email protected]>
Co-authored-by: Dan Bjorge <[email protected]>
Co-authored-by: Mike Gower <[email protected]>

Author: 4 people

understanding/20/page-titled.html

@@ -122,22 +122,16 @@ <h2>Resources for Page Titled</h2>
 
 
       <ul>
-         
          <li> 
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-            <a href="https://socialpatterns.com/writing-better-titles/">Writing Better Web Page Titles</a>. How to write titles for web pages that will enhance search engine effectiveness.
+            <a href="https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Elements/title#accessibility">&lt;title&gt;: The Document Title element: Usage notes (Accessibility)</a>.
          </li>
-         
          <li> 
-            
             <a href="https://redish.net/wp-content/uploads/Theorfanos_Redish_InteractionsPaperAuthorsVer.pdf">Guidelines for Accessible and Usable Web Sites: Observing Users Who Work With Screen
                Readers (PDF)
             </a>. Theofanos, M.F., and Redish, J. (2003).  Interactions, Volume X, Issue 6, November-December
             2003, pages 38-51, 
             <a href="https://dl.acm.org/doi/10.1145/947226.947227">https://dl.acm.org/doi/10.1145/947226.947227</a>
-            							     
          </li>
-         
       </ul>
 
    </section>