remove stage.Done() method (#2390)

cmd/integration/commands/snapshot_check.go

eth/stagedsync/stage.go

eth/stagedsync/stage_blockhashes.go

eth/stagedsync/stage_bodies.go

eth/stagedsync/stage_bodies_snapshot.go

eth/stagedsync/stage_call_traces.go

eth/stagedsync/stage_execute.go

eth/stagedsync/stage_finish.go

eth/stagedsync/stage_hashstate.go

eth/stagedsync/stage_headers.go

eth/stagedsync/stage_headers_snapshot.go

eth/stagedsync/stage_indexes.go

eth/stagedsync/stage_interhashes.go

eth/stagedsync/stage_log_index.go

eth/stagedsync/stage_mining_create_block.go

eth/stagedsync/stage_mining_exec.go

eth/stagedsync/stage_mining_finish.go

eth/stagedsync/stage_senders.go

eth/stagedsync/stage_state_snapshot.go

eth/stagedsync/stage_tevm.go