Log Message:
xfce4-whiskermenu-plugin: update to 2.3.5

Change log:

2.3.5
=====
- Fix saving unchanged plugin title. (bug #15403)
- Fix sidebar scrollbar covering buttons. (bug #14730)
- Fix categories remaining scrolled when hidden.
- Fix incorrect alignment of commands next to search.
- Fix incorrect fallback value for menu opacity.
- Fix incorrect check when setting command.
- Update documentation URL. (bug #16183)

2.3.4
=====
- Fix building against xfce4-panel 4.15.0
- Translation updates: Dutch, Galician, Georgian.