engine: Migrate tests to testify/assert
engine: Migrate tests to testify/assert

kelda/kelda,tejasmanohar/quilt,LuiseV/quilt,PenguinToast/quilt,LuiseV/quilt,mmussomele/quilt,kklin/quilt,NetSys/quilt,PenguinToast/quilt,kklin/kelda,stevenlin598/quilt,tejasmanohar/quilt,kklin/kelda,ejj/quilt-dev,NetSys/quilt,LuiseV/quilt,kayousterhout/quilt,mmussomele/quilt,NetSys/quilt,PenguinToast/quilt,NetSys/quilt,quilt/quilt,stevenlin598/quilt,tejasmanohar/quilt,kelda/kelda,NetSys/quilt,kklin/kelda,kayousterhout/quilt,tejasmanohar/quilt,kelda/kelda,ejj/quilt-dev,stevenlin598/quilt,kklin/quilt,ejj/quilt-dev,quilt/quilt,kklin/kelda,ejj/quilt-dev,kayousterhout/quilt,kklin/quilt,LuiseV/quilt,stevenlin598/quilt,stevenlin598/quilt,kayousterhout/quilt,quilt/quilt,quilt/quilt,PenguinToast/quilt,kklin/quilt,PenguinToast/quilt,mmussomele/quilt,mmussomele/quilt,mmussomele/quilt,LuiseV/quilt,stevenlin598/quilt,kelda/kelda,mmussomele/quilt