Update Documentation/README_ConstraintManager.md
Update Documentation/README_ConstraintManager.md

Co-authored-by: Vanessa Oliva <5ed9b7def9808d3e482697165f2fa175b65cdda9@users.noreply.github.com>
DDReaper/MixedRealityToolkit-Unity,killerantz/HoloToolkit-Unity,killerantz/HoloToolkit-Unity,killerantz/HoloToolkit-Unity,killerantz/HoloToolkit-Unity