Remove datetime.UTC

Replace  `datetime.UTC` by `datetime.timezone.utc`
datetime.
UTC has been introduced into Python 3.11 and we still want to support Python 3.10

ref: it/org/software-supply-chain/production-pipeline/issues#182

Author: elsaferrara

src/e3/aws/troposphere/awslambda/__init__.py

@@ -1,6 +1,6 @@
 from __future__ import annotations
 
-from datetime import UTC, datetime
+from datetime import timezone, datetime
 from enum import Enum
 import logging
 import os
@@ -659,7 +659,7 @@ def __init__(
         )
         self.source_dir: str = source_dir
         self.repository_name: str = repository_name
-        timestamp = datetime.now(UTC).strftime("%Y-%m-%d-%H-%M-%S-%f")
+        timestamp = datetime.now(timezone.utc).strftime("%Y-%m-%d-%H-%M-%S-%f")
         self.image_tag: str = f"{image_tag}-{timestamp}"
         self.image_uri: str | None = None
         self.docker_client = docker_client