TOB-FUEL-22: TRO opcode does not revert when amount is zero as specified

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Description

The transfer output (TRO) opcode transfers coins to addresses by creating a UTXO. The Fuel VM specification states that TRO should panic if the amount ($rC) is zero but the implementation does not perform this validation. Note, that the transfer coins to contract (TR) opcode does perform this validation and will revert for transfers with an amount of zero.

Figure 22.1: The TRO implementation (fuel-vm/src/interpreter/contract.rs#290–367)

   pub(crate) fn transfer_output(
        self,
        a: Word,
        b: Word,
        c: Word,
        d: Word,
    ) -> Result<(), RuntimeError>
    where
        Tx: ExecutableTransaction,
        S: ContractsAssetsStorage,
        <S as StorageInspect<ContractsAssets>>::Error: Into<std::io::Error>,
{
[...]
        let amount = c;
[...]
        // credit variable output
        let variable = Output::variable(to, amount, asset_id);
        set_variable_output(self.tx, self.memory, self.tx_offset, out_idx,
variable)?;
[...]

Recommendations

Short term, determine whether zero amount transfers will cause a panic and update the specifications and implementations to be consistent.
Long term, create unit test cases that trigger all specified panics.

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Is a duplicate of the #522 and fixed by #532