Integrate PettingZoo MPE environment

[wduguay-air]

MPE doc: https://pettingzoo.farama.org/environments/mpe/

Environment to implement: Simple Tag

[cloderic]

Maybe just bump gym to gymnasium to support latest versions of pettingzoo is the answer

[wduguay-air]

Prototype feature available from branch. Will wait for user feedback before opening a PR.