serialization test for ScatterAlignPose2

[dehann]

From Slack (Jim):

Dehann, Johan, Could we drop a unit test for serialization of ScatterAlignPose2 somewhere in the Caesar ecosystem? After upgrade, the other stuff seems to be working but ScatterAlignPose2 is not. Full disclosure: This could be a Jim problem, but I would like to start on the bottom and work up. I'll be happy to drop this in an issue if you want, just not sure exactly where. Below find the code I am running. Basically it makes a factor, packs it, unpacks it, and then re-adds it. Also, find the error it throws.

testScatterAlignPose2.zip