<?xml version='1.0' encoding='UTF-8'?>
<sites>
  <site>
    <id>default</id>
    <url>http://updates.jenkins-ci.org/update-center.json</url>
  </site>
</sites>
<?xml version='1.1' encoding='UTF-8'?>
<sites>
  <site>
    <id>default</id>
    <url>http://updates.jenkins-ci.org/update-center.json</url>
  </site>
</sites>

Update config that jenkins updates each run
Update config that jenkins updates each run

Jenkins now defines this as XML 1.1
