JSON config should not accept timestamp_logger_nodes that different from source_node

[yimmy13]

Guided by Austin-- I was looking at the following code out of y2022_roborio.json:

{ "name": "/drivetrain", "type": "frc971.control_loops.drivetrain.Output", "source_node": "roborio", "frequency": 400, "max_size": 80, "num_senders": 2, "logger": "LOCAL_AND_REMOTE_LOGGER", "logger_nodes": [ "imu" ], "destination_nodes": [ { "name": "imu", "priority": 5, "timestamp_logger": "LOCAL_AND_REMOTE_LOGGER", "timestamp_logger_nodes": [ "imu" ], "time_to_live": 5000000 } ] },
The timestamp_logger_nodes should be the source_node, "roborio", rather than currently as "imu". Our json creation/merging shouldn't accept other choices than the source_node.