fix: accidental check of if container causes massive amount of reqs

`if container` delegates to `len(container) == 0` check

Author: fubuloubu

silverback/main.py

@@ -297,7 +297,7 @@ def broker_task_decorator(
         ):
             raise ContainerTypeMismatchError(task_type, container)
 
-        elif container and isinstance(container, ContractEventWrapper):
+        elif isinstance(container, ContractEventWrapper):
             if len(container.events) != 1:
                 raise InvalidContainerTypeError(
                     f"Requires exactly 1 event to unwrap: {container.events}"