Retrieve WorkerRun configuration on initialization

Closes #75 (closed)

arkindex_worker/worker/base.py

@@ -167,6 +167,8 @@ class BaseWorker(object):
                 "RetrieveWorkerRun", id=os.environ["ARKINDEX_WORKER_RUN_ID"]
             )
             self.user_configuration = worker_run.get("configuration")
+            if self.user_configuration:
+                logger.info("Loaded user configuration from WorkerRun")
 
         task_id = os.environ.get("PONOS_TASK")
         paths = None