[1448] Fix admin monitor UI (#1493)

plugin/src/main/resources/io/jenkins/plugins/casc/ObsoleteConfigurationMonitor/message.jelly

@@ -1,14 +1,11 @@
 <?jelly escape-by-default='true'?>
 <j:jelly xmlns:j="jelly:core">
-
   <div class="${it.css}">
-    <form method="post" >
     ${%Configuration as Code obsolete file format}:
     <ul>
       <j:forEach items="${it.errors}" var="error">
-        <li>${error.source.file} (line ${error.source.line}): ${error.message}</li>
+        <li>${error.message}</li>
       </j:forEach>
     </ul>
-    </form>
   </div>
 </j:jelly>