Added stub release notes for Django 3.2.3.

docs/releases/3.2.3.txt

@@ -0,0 +1,12 @@
+==========================
+Django 3.2.3 release notes
+==========================
+
+*Expected June 1, 2021*
+
+Django 3.2.3 fixes several bugs in 3.2.2.
+
+Bugfixes
+========
+
+* ...

docs/releases/index.txt

@@ -32,6 +32,7 @@ versions of the documentation contain the release notes for any later releases.
 .. toctree::
    :maxdepth: 1
 
+   3.2.3
    3.2.2
    3.2.1
    3.2