message: fix full undelegation
diff: @@ -224,10 +224,9 @@ pub trait Auction:
  debug_assert!(_unbonding_purse_balance > new_amount);
  if new_amount.is_zero() {
  - // Inner map's mapped value should be zero as we subtracted mutable value.
  let _value = delegators_map
  - .remove(&validator_public_key)
  - .ok_or(Error::ValidatorNotFound)?;
  + .remove(&delegator_public_key)
  + .ok_or(Error::DelegatorNotFound)?;
  debug_assert!(_value.is_zero());
  let mut outer = internal::get_delegator_reward_map(self)?;
  