message: Update types/src/mint.rs
diff: @@ -227,7 +227,7 @@ pub trait Mint: RuntimeProvider + StorageProvider + EraProvider {
  /// Slashes each validator.
  ///
  - /// This can be only invoked through as a system call.
  + /// This can be only invoked through a system call.
  fn slash(&mut self, validator_public_keys: Vec<PublicKey>) -> Result<(), Error> {
  if self.get_caller() != SYSTEM_ACCOUNT {
  return Err(Error::InvalidCaller);
  