fix(core): Consider timeout in shutdown an error (#8050)

If the process doesn't shutdown within a time limit, exit with error
code.

1. conceptually something timing out is an error.
2. on successful exit we close down the DB connection gracefully. On an
exit timeout we rather not do that, since it will wait for any active
connections to close and would possible block the exit.

packages/cli/src/config/schema.ts

@@ -439,7 +439,7 @@ export const schema = {
 				env: 'QUEUE_RECOVERY_INTERVAL',
 			},
 			gracefulShutdownTimeout: {
-				doc: 'How long should n8n wait for running executions before exiting worker process',
+				doc: 'How long should n8n wait for running executions before exiting worker process (seconds)',
 				format: Number,
 				default: 30,
 				env: 'QUEUE_WORKER_TIMEOUT',