use uint8 instead of deprecated byte

[mikaelarguedas]

don't use deprecated byte but uint8

connects to ros2/rosidl#190

[codebot]

👍 lgtm

in an ideal world, we would be able to change the identifier as well, but I'm not sure that would be worth the problems it would cause going through the bridge, etc., so I think it's fine to leave the identifier as bytes_value.

[mikaelarguedas]

I kept it as is so that people feel like they can pass hexadecimal values without worrying about sign.
This message being used only on the ROS2 side so we could change the field name without resulting in changes in the bridge but it seemed to be a less intrusive change (bytes are already treated as uint8 in the ROS2 code using parameters so it is transparent)

[codebot]

I agree, lgtm. 🐔

[mikaelarguedas]

this also relates to the upcoming C parameter implementation that may require this change and / or additional changes to the possible parameter types (e.g. arrays of parameters)

[clalancette]

We haven't done this until now, so I'm going to venture to say we aren't going to do it. Because of that, I'm going to close this out, but feel free to reopen if you are going to pursue it in the future.