Fjord Token Staking

summary - In FjordStaking.sol :: setRewardAdmin use 2 step rewardAdmin transfer.

Recommendations -

function setRewardAdmin(address _rewardAdmin) external onlyOwner {
    if (_rewardAdmin == address(0)) revert InvalidZeroAddress();
    address oldrewardAdmin = rewardAdmin;
    rewardAdmin = _rewardAdmin;        
}