5b6686095a
This is a new property to control the padding around each page,
as opposed to the padding around the entire container.
Following the original design of IconGridLayout [1], changing
the page-padding property doesn't trigger relayouts; the container
is responsible for queueing a relayout appropriately.
[1] 3555550d5e
Part-of: <https://gitlab.gnome.org/GNOME/gnome-shell/-/merge_requests/1510>