TreeIcons test extension
This extension is to demonstrate a bug in TreeView icon handling, present in vscode 1.67. The Extension creates an additional File Explorer that displays 1st workspace folder, if it exist.
On first (and each odd) level of the tree, it provides TreeItems with a valid resourceUri and an iconPath set to new vscode.ThemeIcon("extensions"). These
items do NOT show extensions icon, but the default theme-folder (= none) one. On 2nd and each even level, TreeItems have the same iconPath, but no resourceUri -- and they display as expected, with the requested theme icon (extensions).