Prevent collapsing of folder names in requests tree navigation

[vtkachenko]

This PR changes the UI behavior of the Folders in Requests' tree - so that when you click on the Folder name, the Folder does not getting collapsed, hiding the child elements. Insead, the Folder is collapsed when you click on a Folder icon instead - which is much more logical and user-friendly.

[CLAassistant]

All committers have signed the CLA.

[CLAassistant]

Thank you for your submission! We really appreciate it. Like many open source projects, we ask that you sign our Contributor License Agreement before we can accept your contribution.
_{You have signed the CLA already but the status is still pending? Let us recheck it.}