overviewControls: Use ease-out-sine when entering overview and app grid

overviewControls: Use ease-out-sine when entering overview and app grid

Using animations with slower initial curves on display-wide
layout shifts may provide a smoother experience to users of
low(er) refresh rate and/or large(r) displays, as they avoid
skipping large chunks of frames, making it less choppy at
the beginning of the animation.

Part-of: <https://gitlab.gnome.org/GNOME/gnome-shell/-/merge_requests/4000>
(cherry picked from commit c518e3ddcc7bee86331a3c2f73896793d00f4f91)