Closes the channel using the provided balance proof.

def close(
            self,
            nonce: Nonce,
            balance_hash: BalanceHash,
            additional_hash: AdditionalHash,
            signature: Signature,
            block_identifier: BlockSpecification,
    ):
        """ Closes the channel using the provided balance proof. """
        self.token_network.close(
            channel_identifier=self.channel_identifier,
            partner=self.participant2,
            balance_hash=balance_hash,
            nonce=nonce,
            additional_hash=additional_hash,
            signature=signature,
            given_block_identifier=block_identifier,
        )