core: Revert artifact version to 3.3.0-SNAPSHOT

Revert commit 270afce27645691acb36054ccbe6d15062dfdc55, as 3.3 branch
has been rebased.

Change-Id: I3220d515e3813d3720ca6ec4885c64c434afd6db
Signed-off-by: Ofer Schreiber <oschreib@redhat.com>