Fixed definition of psSlicingFinished to fix notification updates after the slicing finishes.
Fixed definition of psSlicingFinished to fix notification updates
after the slicing finishes.

prusa3d/Slic3r,prusa3d/Slic3r,prusa3d/Slic3r,prusa3d/Slic3r,prusa3d/Slic3r,prusa3d/Slic3r,prusa3d/Slic3r