whats new fix

Author: mongoKart

source/whats-new.txt

@@ -22,9 +22,6 @@ Learn what's new in:
 
 * :ref:`Version 2.23 <version-2.23>`
 * :ref:`Version 2.22 <version-2.22>`
-* :ref:`Version 2.21 <version-2.21>`
-* :ref:`Version 2.20 <version-2.20>`
-* :ref:`Version 2.19 <version-2.19>`
 
 .. _upcoming-breaking-changes: