message: add missing import.
diff: @@ -51,7 +51,7 @@ use crate::{
  reactor::ReactorExit,
  types::{
  chainspec::{Error, ProtocolConfig, CHAINSPEC_NAME},
  - ActivationPoint, Block, BlockHeader, Chainspec, ChainspecInfo, ExitCode,
  + ActivationPoint, Block, BlockHash, BlockHeader, Chainspec, ChainspecInfo, ExitCode,
  },
  utils::{self, Loadable},
  NodeRng,
  