mark two tests that fail on dbstore

also add @pytest.mark.checksum for new checksum
tests

Signed-off-by: Matt Benjamin <mbenjamin@redhat.com>

s3tests_boto3/functional/test_s3.py

@@ -13458,6 +13458,7 @@ def test_object_checksum_sha256():
     assert error_code == 'InvalidRequest'
 
 @pytest.mark.checksum
+@pytest.mark.fails_on_dbstore
 def test_multipart_checksum_sha256():
     bucket = get_new_bucket()
     client = get_client()
@@ -13522,6 +13523,7 @@ def test_multipart_checksum_sha256():
     assert composite_sha256sum == response['ChecksumSHA256']
 
 @pytest.mark.checksum
+@pytest.mark.fails_on_dbstore
 def test_multipart_checksum_3parts():
     bucket = get_new_bucket()
     client = get_client()
@@ -13559,6 +13561,7 @@ def test_multipart_checksum_3parts():
     response = client.head_object(Bucket=bucket, Key=key, ChecksumMode='ENABLED')
     assert composite_sha256sum == response['ChecksumSHA256']
 
+@pytest.mark.checksum
 def test_post_object_upload_checksum():
     megabytes = 1024 * 1024
     min_size = 0