fix: broken link (EbookFoundation#5402)

* fix: broken link

Fixed the pdf link of broken C++ Cheat Sheet.
Issue No. EbookFoundation#5378

* Update more/free-programming-cheatsheets.md

Co-authored-by: David Ordás <[email protected]>

Co-authored-by: Eric Hellman <[email protected]>
Co-authored-by: David Ordás <[email protected]>

Author: 3 people

more/free-programming-cheatsheets.md

@@ -42,7 +42,7 @@
 
 ### <a name="cpp"></a>C++
 
-* [C++ Quick Reference](http://www.hoomanb.com/cs/QuickRef/CppQuickRef.pdf) (PDF)
+* [C++ Quick Reference](http://www.hoomanb.com/cs/quickref/CppQuickRef.pdf) - Hooman Baradaran (PDF)
 
 
 ### Clojure