[1.11.x] Added stub release notes for security releases.

carltongibson · carltongibson · commit 4b3716e6540e · 2019-06-03T10:54:19.000+02:00
Backport of 98c0fe1 from master
diff --git a/docs/releases/1.11.21.txt b/docs/releases/1.11.21.txt
@@ -0,0 +1,7 @@
+============================
+Django 1.11.21 release notes
+============================
+
+*June 3, 2019*
+
+Django 1.11.21 fixes security issues in 1.11.20.
diff --git a/docs/releases/index.txt b/docs/releases/index.txt
@@ -26,6 +26,7 @@ versions of the documentation contain the release notes for any later releases.
 .. toctree::
    :maxdepth: 1
 
+   1.11.21
    1.11.20
    1.11.19
    1.11.18
