chore: update components and fix a small issue while fetching demo list

qtquickdesigner-components @ 5f115ed1

-Subproject commit 59721758afe9d7034ca76f1a19c3c5c97610ceaa
+Subproject commit 5f115ed120adb58972ac3a0a2b80ec42cf3769a1

www/scripts/script.js

@@ -118,7 +118,8 @@ function listExamples() {
     request.responseType = "json";
     request.onload = function (oEvent) {
         var json = request.response;
-        if (json.length > 0) {
+        // check if json is not null
+        if (json !== null && json.length > 0) {
             var projectsmenulist = document.querySelector("#projectsmenulist");
             for (project in json) {
                 var li = document.createElement("li");