Missing null for First go to frame in Animation (#12465)
Missing null for First go to frame in Animation (#12465)

Co-authored-by: Cedric Guillemet <6978064c39c586f803934a265f0429d91ca49b31@microsoft.com>
RaananW/Babylon.js,RaananW/Babylon.js,sebavan/Babylon.js,BabylonJS/Babylon.js,BabylonJS/Babylon.js,sebavan/Babylon.js,RaananW/Babylon.js,BabylonJS/Babylon.js,sebavan/Babylon.js