[dev] correct backends/cdn paths

demos/cases/GanttBackend.jsx

@@ -10,7 +10,7 @@ const parseDates = (data) => {
 };
 
 export default function GanttBackend() {
-  const server = 'https://master--svar-gantt-go--dev.webix.io';
+  const server = 'https://gantt-backend.svar.dev';
 
   const [api, setApi] = useState();
   const [tasks, setTasks] = useState([]);

demos/cases/GanttBatchProvider.jsx

@@ -5,7 +5,7 @@ import { Gantt, ContextMenu, Editor } from '../../src';
 export default function GanttBatchProvider() {
   const restProvider = useMemo(
     () =>
-      new RestDataProvider('https://master--svar-gantt-go--dev.webix.io', {
+      new RestDataProvider('https://gantt-backend.svar.dev', {
         batchURL: 'batch',
       }),
     [],

demos/cases/GanttProvider.jsx

@@ -4,7 +4,7 @@ import { Gantt, ContextMenu, Editor } from '../../src';
 
 export default function GanttProvider() {
   const restProvider = useMemo(
-    () => new RestDataProvider('https://master--svar-gantt-go--dev.webix.io'),
+    () => new RestDataProvider('https://gantt-backend.svar.dev'),
     [],
   );