FIX: fix call of ColorBarWidget in `plotwidget.py` (cherry picked from commit 04a0b4a)
FIX: fix call of ColorBarWidget in `plotwidget.py`
(cherry picked from commit 04a0b4a)

drufat/vispy,drufat/vispy,michaelaye/vispy,Eric89GXL/vispy,michaelaye/vispy,michaelaye/vispy,Eric89GXL/vispy,drufat/vispy,Eric89GXL/vispy