releases: update to include 3.1.13

Adding 3.1.13 to documentation switcher and release list.

(From yocto-docs rev: 24fe6a752cdec66a3d34d390fa645726ed3725b8)

Signed-off-by: Michael Halstead <mhalstead@linuxfoundation.org>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

documentation/releases.rst

@@ -38,6 +38,7 @@ Release Series 3.1 (dunfell)
 - :yocto_docs:`3.1.10 Documentation </3.1.10>`
 - :yocto_docs:`3.1.11 Documentation </3.1.11>`
 - :yocto_docs:`3.1.12 Documentation </3.1.12>`
+- :yocto_docs:`3.1.13 Documentation </3.1.13>`
 
 ==========================
  Outdated Release Manuals

documentation/sphinx-static/switchers.js

@@ -6,7 +6,7 @@
     '3.4.1': '3.4.1',
     '3.3.4': '3.3.4',
     '3.2.4': '3.2.4',
-    '3.1.12': '3.1.12',
+    '3.1.13': '3.1.13',
     '3.0.4': '3.0.4',
     '2.7.4': '2.7.4',
   };