[JENKINS-38187] Fix latest comments

core/src/main/java/jenkins/model/Jenkins.java

@@ -1230,15 +1230,17 @@ public class Jenkins extends AbstractCIBase implements DirectlyModifiableTopLeve
             return jenkins.model.Messages.EnforceSlaveAgentPortAdministrativeMonitor_displayName();
         }
 
+        public String getSystemPropertyName() {
+            return Jenkins.class.getName() + ".slaveAgentPort";
+        }
+
         public int getExpectedPort() {
             int slaveAgentPort = j.slaveAgentPort;
             return Jenkins.getSlaveAgentPortInitialValue(slaveAgentPort);
         }
 
         public void doAct(StaplerRequest req, StaplerResponse rsp) throws IOException {
-            if (req.hasParameter("reset")) {
-                j.setSlaveAgentPort(getExpectedPort());
-            }
+            j.setSlaveAgentPort(getExpectedPort());
             rsp.sendRedirect2(req.getContextPath() + "/manage");
         }
 

core/src/main/resources/jenkins/model/Jenkins/EnforceSlaveAgentPortAdministrativeMonitor/message.jelly

@@ -24,7 +24,7 @@ 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" xmlns:i="jelly:fmt">
     <div class="warning">
-        ${%description(it.expectedPort)}
+        ${%description(it.systemPropertyName, it.expectedPort)}
         <form method="post" action="${rootURL}/${it.url}/act" name="${it.id}">
             <div style="float:right">
                 <f:submit name="reset" value="${%reset(it.expectedPort)}"/>

core/src/main/resources/jenkins/model/Jenkins/EnforceSlaveAgentPortAdministrativeMonitor/message.properties

-description=Slave Agent Port has been manually changed. Its value will be reset to {0,number,#} on restart.
+description=JNLP Agent Port has been changed but was specified through system property {0} on startup. Its value will be reset to {1,number,#} on restart.
 reset=Reset to {0,number,#}