Tests re appending `returnData` to the `composedCallData`

[filmakarov]

1. Test bytes.concat vs abi.encodePacked
2. Add explicit test to showcase that when the returned data is address it is appended and emitted properly

        for (uint256 i; i < length; i++) {
            composedCalldata = bytes.concat(composedCalldata, processInput(inputParams[i]));
        }