Transaction enum's variant name are too verbose

[tdelabro]

pub enum Transaction {
    AccountTransaction(AccountTransaction),
    L1HandlerTransaction(L1HandlerTransaction),
}

could be

pub enum Transaction {
    Account(AccountTransaction),
    L1Handler(L1HandlerTransaction),
}

without losing any information.

[tdelabro]

pub enum AccountTransaction {
    Declare(DeclareTransaction),
    DeployAccount(DeployAccountTransaction),
    Invoke(InvokeTransaction),
}

is already doing it right