Handle hedera accounts on metamask according to their accountId rather than evmaddress

[kpachhai]

Maybe the best way is to change the type of extraData for hedera network accounts to something like:

{
    extraData: {
        accountId: string | string[]
    }
}

[kpachhai]

This is not needed as there's only one accountid that will ever be associated with an evm address.