Refactor IngestorManager and OpcManager for improved server management
- Introduced a new method `remove_server` in IngestorManager to encapsulate server removal logic, enhancing code clarity and reusability.
- Updated `update_opc_servers` to utilize the new `remove_server` method for better maintainability.
- Refactored security settings in OpcManager to use direct attribute assignments instead of method calls, streamlining the code.
- Adjusted unit tests to reflect changes in the IngestorManager and OpcManager, ensuring proper asynchronous behavior and mocking.