Minor tweak to the refresh/update prompt in the Horizon app

Author: pborissow

ui/javascript/app/Horizon.js

@@ -647,6 +647,7 @@ javaxt.express.app.Horizon = function(parent, config) {
                     me.el.style.filter = "blur(3px)";
                     confirm({
                         width: 515,
+                        resizable: false,
                         title: "Update Available",
                         text: config.messages.updateAvailable,
                         leftButton: {