remove "sumo-" value on input blur

assets/js/sumorobot.js

@@ -529,6 +529,15 @@ window.onload = function() {
         }
     });
     
+    /* when robot-id input field gets unfocused */
+    $("#robot-id").focus(function() {
+        /* if the robot-id input value is the previously set "sumo-" */
+        if ($("#robot-id").val() === "sumo-") {
+            /* remove the value */
+            $("#robot-id").val("");
+        }
+    });
+
     /* robot number button listener */
     $(".btn-robot-go").click(function() {
         /* extract and validate the selected robot ID */