delete `successfully pushed` message
delete `successfully pushed` message

close #1742
Delete the line: `Successfully pushed...`

Signed-off-by: Qi Wang <qiwan@redhat.com>

Closes: #1744
Approved by: TomSweeneyRedHat

projectatomic/buildah,rhatdan/buildah,nalind/buildah,nalind/buildah-1,nalind/buildah-1,nalind/buildah-1,TomSweeneyRedHat/buildah,projectatomic/buildah,rhatdan/buildah,nalind/buildah,projectatomic/buildah,TomSweeneyRedHat/buildah,rhatdan/buildah,TomSweeneyRedHat/buildah