Update Documentation/README_ObjectCollection.md
Update Documentation/README_ObjectCollection.md

Co-Authored-By: Bernadette Thalhammer <af506787d5ce25b28f81ff8dc574922ca43db5b0@users.noreply.github.com>
killerantz/HoloToolkit-Unity,killerantz/HoloToolkit-Unity,DDReaper/MixedRealityToolkit-Unity,killerantz/HoloToolkit-Unity,killerantz/HoloToolkit-Unity