Add generic N8N_GRACEFUL_SHUTDOWN_TIMEOUT which controls how long n8n
process will wait for graceful exit before exitting forcefully. This
variables replaces the QUEUE_WORKER_TIMEOUT variable that was used for
worker process.
DEPRECATED: QUEUE_WORKER_TIMEOUT deprected
QUEUE_WORKER_TIMEOUT environment variable has been replaced with
N8N_GRACEFUL_SHUTDOWN_TIMEOUT.