modify test_sse_kms_method_head() for aws standard
modify test_sse_kms_method_head() for aws standard

Signed-off-by: hechuang <b7c645cead522c9985f880440d41b740a4a4ddd6@xsky.com>

ceph/s3-tests,andrewgaul/s3-tests,timuralp/s3-tests,ceph/s3-tests,jmunhoz/s3-tests,jmunhoz/s3-tests,timuralp/s3-tests,robbat2/s3-tests,andrewgaul/s3-tests,robbat2/s3-tests