feature(pu): add pistonball_env, its unittest and qmix config #3457

	# This workflow will check pytest
	# For more information see: https://help.github.com/actions/language-and-framework-guides/using-python-with-github-actions

	name: envpool_test

	on: [push, pull_request]

	jobs:
	test_envpooltest:
	runs-on: ubuntu-latest
	if: "!contains(github.event.head_commit.message, 'ci skip')"
	strategy:
	matrix:
	python-version: [3.8] # Envpool only supports python>=3.7

	steps:
	- uses: actions/checkout@v4
	- name: Set up Python ${{ matrix.python-version }}
	uses: actions/setup-python@v5
	with:
	python-version: ${{ matrix.python-version }}
	- name: do_envpool_test
	run: \|
	python -m pip install .
	python -m pip install ".[test,k8s]"
	python -m pip install ".[envpool]"
	python -m pip install transformers
	./ding/scripts/install-k8s-tools.sh
	make envpooltest

Provide feedback