Doc: update release date for v15.

tglsfdc · tglsfdc · commit 2a7ce2e2ce47 · 2022-10-10T16:57:37.000-04:00
Drat, forgot this ...
diff --git a/doc/src/sgml/release-15.sgml b/doc/src/sgml/release-15.sgml
@@ -3,7 +3,7 @@
 
   <formalpara>
    <title>Release date:</title>
-   <para>CURRENT AS OF 2022-10-03</para>
+   <para>2022-10-13</para>
   </formalpara>
 
   <sect2>
