SIENTIAPDE-1445

Refactor imports and enhance timestamp handling in API and test files

- Removed redundant import statements in api.py and prepare_worker.py for cleaner code.
- Updated timestamp format in test cases to include timezone information for consistency.
- Adjusted test configurations to align with new API structure for improved accuracy in data handling.

scouter/activities/api.py

@@ -9,9 +9,10 @@ with workflow.unsafe.imports_passed_through():
     from sientia_do.observability.logger import Logger
     from sientia_do.observability.metrics_controller import MetricsController
     from sientia_do.observability.sientia_monitoring import SientiaMonitoring
+    from sientia_do.temporal.constants import DATETIME_FORMAT_WITH_TZ
 
     from scouter.utils.clients.pi_web_api_client import PIWebAPIClient
-    from sientia_do.temporal.constants import DATETIME_FORMAT_WITH_TZ
+
 
 class API(SientiaMonitoring):
     """