[4.2.x] Added stub release notes and release date for 4.2.24.

Backport of 4c71e33 from main.

Author: sarahboyce

docs/releases/4.2.24.txt

@@ -0,0 +1,7 @@
+===========================
+Django 4.2.24 release notes
+===========================
+
+*September 3, 2025*
+
+Django 4.2.24 fixes a security issue with severity "high" in 4.2.23.

docs/releases/index.txt

@@ -26,6 +26,7 @@ versions of the documentation contain the release notes for any later releases.
 .. toctree::
  :maxdepth: 1
 
+ 4.2.24
  4.2.23
  4.2.22
  4.2.21