ENH: Remove border properties for the scalarbar representation

Read the property values from the underlying vtkScalarBar actor.
This change fixes issue 14646.

Change-Id: Ic3d836f6420e126c7729f2d1436f34f6151427b3
Merge topic '14646-scalar-bar-borders' into next

dbf4681d ENH: Remove border properties for the scalarbar representation