Update required protobuf version

[rk1a]

These version specifications are compatible with cleanRL and the protobuf compiler on the cluster.

Ready for Review.

[neverix]

Might be a problem since VPT requires gym==0.19 and SB3 gym==0.21. I would suggest moving this into an extras_require.

[rk1a]

Might be a problem since VPT requires gym==0.19 and SB3 gym==0.21. I would suggest moving this into an extras_require.

Yea, this is problematic.
Though, I think an extras_require would only make sense if we also provide the RL code in minetester.
Can we just require gym without version, and let each library install its required version?

As a side note, the current minetest env is only compatible up to gym==0.22 which introduces the first large change to the API. Code that uses newer gym versions should convert minetest envs, e.g. with compatibility wrappers like the ones available in gym(nasium)>=0.26: https://gymnasium.farama.org/content/gym_compatibility/#gym-v0-22-environment-compatibility

[AI-WAIFU]

lgtm