Download: rm outdated StackPath note

add link to jQuery CDN landing page instead,
where current sponsor logo is shown.

Ref jquery/infrastructure-puppet#30.

pages/download.html

@@ -18,7 +18,7 @@ <h3>1.4.5</h3>
 <li><a href="/resources/download/jquery.mobile-1.4.5.zip">Zip File: jquery.mobile-1.4.5.zip</a> (JavaScript, CSS, and images)</li>
 </ul>
 
-<p><strong>jQuery CDN</strong> <small>provided by <a href="https://www.stackpath.com">StackPath</a></small></p>
+<p><a href="https://code.jquery.com/"><strong>jQuery CDN</strong></a></p>
 <p>JavaScript:</p>
 <ul>
 <li><a href="https://code.jquery.com/mobile/1.4.5/jquery.mobile-1.4.5.js">Uncompressed: jquery.mobile-1.4.5.js</a> (useful for debugging)</li>