Fix/db digest (#217)

* fix: Use image digest for MR DB, fixes disconnected testing

Signed-off-by: lugi0 <lgiorgi@redhat.com>

* fix: typo in constant import

Signed-off-by: lugi0 <lgiorgi@redhat.com>

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Signed-off-by: lugi0 <lgiorgi@redhat.com>
Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

Author: lugi0

tests/model_registry/conftest.py

@@ -13,7 +13,7 @@
 from tests.model_registry.utils import get_endpoint_from_mr_service, get_mr_service_by_label
 from utilities.infra import create_ns
 from utilities.constants import Annotations, Protocols
-from constants import MR_DB_IMAGE_DIGEST
+from .constants import MR_DB_IMAGE_DIGEST
 
 
 LOGGER = get_logger(name=__name__)