Update logic for verifyCertificate for CCU verification

[ishantiw]

Description

Update logic associated with certificate verification based on the latest implementation of LIP0053

def verifyCertificate(ccu: Transaction) -> None:
    certificateBytes = ccu.params.certificate      
    certificate = decode(certificateSchema, certificateBytes)
    partnerchainID = ccu.params.sendingChainID
    partnerchainAccount = chainAccount(partnerchainID)
    # Certificate height must be greater than last certificate height.
    if certificate.height <= partnerchainAccount.lastCertificate.height:
        raise Exception("Certificate height is not greater than last certificate height.")
    # Certificate timestamp must be smaller than timestamp of the block including the CCU.
    timestamp = timestamp of the block including ccu
    if certificate.timestamp >= timestamp:
        raise Exception("Certificate timestamp is not smaller than timestamp of the block including the CCU.")

Acceptance Criteria

• Should have unit test

Additional Information

• Related PR Update Interoperability LIPs lips#148
• Related LIP https://github.com/LiskHQ/lips/blob/main/proposals/lip-0053.md
• Related function https://github.com/LiskHQ/lisk-sdk/blob/development/framework/src/modules/interoperability/utils.ts#L263