Decoding of fixed bytes order may be wrong

[ermvrs]

Ensure bytes decoded correctly via adding new tests.

It includes more tests for fixed sized bytes and dynamic sizes (bytes) also string

Example test

#[test]
fn test_decode_bytes32_zeroes() {
    let mut data: Bytes = BytesTrait::blank();

    data.append_u256(0x00000fffffffffffffffffffffffffffffffffffffffffffffffffffffffffff);
    let mut calldata = cd(data);

    let decoded = calldata.decode(array![EVMTypes::Bytes32].span());
    assert_eq!(*decoded.at(0), 0x1);
    assert_eq!(*decoded.at(1), 0x000fffffffffffffffffffffffffffffffffffffffffffffffffffffffff);
    assert_eq!(*decoded.at(2), 0x00);
    assert_eq!(*decoded.at(3), 0x1);
}

But im not sure the second part should be 0x00 or 0xff (first byte or last byte)

[ermvrs]

Especially at decode_bytes_32(...) function