remove on_exit from grandpa (#5098)

substrate/bin/node/cli/src/service.rs

@@ -225,7 +225,6 @@ macro_rules! new_full {
 				link: grandpa_link,
 				network: service.network(),
 				inherent_data_providers: inherent_data_providers.clone(),
-				on_exit: service.on_exit(),
 				telemetry_on_connect: Some(service.telemetry_on_connect_stream()),
 				voting_rule: grandpa::VotingRulesBuilder::default().build(),
 				prometheus_registry: service.prometheus_registry(),