Async flow uses gson to de-serialize the event to a ChampObject which is
causing inconsistencies for timestamp property values. Fix is to use
jackson which the sync flow also uses.
Change-Id: Ic766d34a8c04b9d076d7cadb53cb9dcb180186b6
Issue-ID: AAI-1363 Signed-off-by: Ravi Geda <GRaviK@amdocs.com>