XEP-0453: Replace my author block with the entity

There is absolutely no change to the resulting document, but if I ever
changed my name or contact addresses it would be easier to do so in one
place.

Author: linkmauve

xep-0453.xml

@@ -23,12 +23,7 @@
   <supersedes/>
   <supersededby/>
   <shortname>NOT_YET_ASSIGNED</shortname>
-  <author>
-    <firstname>Emmanuel Gil</firstname>
-    <surname>Peyrot</surname>
-    <email>[email protected]</email>
-    <jid>[email protected]</jid>
-  </author>
+  &linkmauve;
   <revision>
     <version>0.1.2</version>
     <date>2023-07-04</date>