cleanup: Mark unused (but useful) variables as ignored

While we aren't using those destructured variables, they are still useful
to document the meaning of those elements. We don't want eslint to keep
warning about them though, so mark them accordingly.

https://gitlab.gnome.org/GNOME/gnome-shell/merge_requests/627

js/ui/endSessionDialog.js

@@ -668,7 +668,7 @@ class EndSessionDialog extends ModalDialog.ModalDialog {
         this._loginManager.listSessions(result => {
             let n = 0;
             for (let i = 0; i < result.length; i++) {
-                let [id, uid, userName, seat, sessionPath] = result[i];
+                let [id_, uid_, userName, seat_, sessionPath] = result[i];
                 let proxy = new LogindSession(Gio.DBus.system, 'org.freedesktop.login1', sessionPath);
 
                 if (proxy.Class != 'user')