Update core/src/main/resources/jenkins/model/GlobalQuietPeriodConfiguration/config.jelly

Co-authored-by: Daniel Beck <1831569+daniel-beck@users.noreply.github.com>

Author: StefanSpieker

core/src/main/resources/jenkins/model/GlobalQuietPeriodConfiguration/config.jelly

@@ -23,7 +23,7 @@ THE SOFTWARE.
 -->
 
 <?jelly escape-by-default='true'?>
-<j:jelly xmlns:j="jelly:core" xmlns:st="jelly:stapler" xmlns:d="jelly:define" xmlns:l="/lib/layout" xmlns:t="/lib/hudson" xmlns:f="/lib/form">
+<j:jelly xmlns:j="jelly:core" xmlns:f="/lib/form">
     <f:entry title="${%Quiet period}" field="quietPeriod">
         <f:number min="0" clazz="number"/>
     </f:entry>