6c1c5e8923
Part of #134755 / #134766.
Adds options to the new Import Settings popover (added in 7a6beb65f4)
to toggle collection instancing for dragging in collections. It can be
toggled separately for linking and appending, since it's typical to use
instancing for linking, but not appending (current default, also with
this change).
Previously, toggling collection instancing was only possible via the
Adjust Last Operation panel but this wasn't obvious, many people were
not aware. Adding this option based on feedback by the Blender Studio.
Pull Request: https://projects.blender.org/blender/blender/pulls/135996