Describe the bug
The Kendo UI DropDownTree has several ARIA errors appearing according to the Axe DevTools.

To Reproduce
Steps to reproduce the behavior:

1. Go to the following StackBlitz.
   
2. Inspect the page, in the inspector click the "axe DevTools" tab and then click the "Scan ALL of my page" button.
3. Under "Serious" issues you will see: ARIA toggle fields must have an accessible name

Expected behavior
There should be no ARIA errors related to the Kendo UI DropDownTree.

Screenshots
Please take a look at the following Screencast related to the issue.

Browser

• OS: All Supported
• Browser: All Supported
• Version: latest (e.g. Edge: 104.0.1293.70)

Modeled after the jQuery widget:

http://demos.telerik.com/aspnet-ajax/dropdowntree/examples/overview/defaultcs.aspx