Function solana_vote_program::vote_state::update_validator_identity

pub fn update_validator_identity<S: BuildHasher>(
    vote_account: &KeyedAccount<'_>, 
    node_pubkey: &Pubkey, 
    signers: &HashSet<Pubkey, S>
) -> Result<(), InstructionError>

Update the node_pubkey, requires signature of the authorized voter