[TECHNICAL SUPPORT] LPS-44340 Remove unnecessary code from tree_js.jsp

Hi Zsaga,

You reviewed my AUI-1114 pr and forwarded to Eduardo. Eduardo deleted some lines from demo\tree\index.html:

https://github.com/liferay/alloy-ui/commit/20e3858866a8dd1dce746dacae470e3cbcf221ed#diff-0

 The deleted lines are also in our tree_js.jsp, so these lines also can be deleted from this file.
I propose you to forward it to Eduardo, with this text to remember him about AUI-1114.

Thank you in advance
Péter