Added 0.23.4 whatsnew [ci skip] (#22214)

TomAugspurger · web-flow · commit 2156431c3a67 · 2018-08-06T06:17:49.000-05:00
[ci skip]
diff --git a/doc/source/whatsnew.rst b/doc/source/whatsnew.rst
@@ -20,6 +20,8 @@ These are new features and improvements of note in each release.
 
 .. include:: whatsnew/v0.24.0.txt
 
+.. include:: whatsnew/v0.23.4.txt
+
 .. include:: whatsnew/v0.23.3.txt
 
 .. include:: whatsnew/v0.23.2.txt
