process method
Starts processing queued jobs.
This method is typically used in a worker loop.
Example:
await queueDriver.process(); // start the worker
Implementation
@override
Future<void> process() async {
final command = await _getConnection();
// Move ready delayed jobs to main queue
await _processDelayedJobs(command);
// Process one job from main queue
await _processNextJob(command);
}