[euphoricmangat]

Gym example envs imported parse_version from pkg_resources, which is deprecated and removed in newer setuptools. Use packaging.version.parse instead, and drop unused imports.

Fixes #4779

[euphoricmangat]

Hello

I am new to the oss world. I have used pybullet many time so a PR for issue #4779 seems like a good entry point.

Several PyBullet gym envs import parse_version from pkg_resources just to check whether gym.__version__ is older than 0.9.6 (legacy API aliases). pkg_resources is deprecated and gone in newer setuptools, so those imports break.

Changes:

• In the 10 files that actually use it, switched to from packaging.version import parse as parse_version so the same comparison still works.
• In cartpole_bullet.py and deep_mimic_env.py, removed the import entirely — it was unused.

No behavior change intended for current gym versions; this only updates the version-parsing import.