feat: make file utils

[WiemKhlifi]

What?

Add new functions to create environments using the create_envs_utils file in mava.utils.

Why?

Instead of creating different file systems for each environment, we use a single file system and remove the common lines that create the environments.

How?

• Added a create_envs_utils file in mava.utils: Create environments from config files.
• Remove the common lines from systems files and use the create_environment function.
• Edit configs to differentiate between the ippo and mappo systems.

[WiemKhlifi]

Very nice, just minor things like make... instead of create... to stay consistent with gym, but this PR is almost ready to go 🔥

All the changes have been made 🙌 . I think this report is now ready or not yet?