remove codacy (#2287)

* remove codacy

* Cleanup name

.circleci/config.yml

             pip install --upgrade setuptools
             cd ml-agents-envs && pip install -e .
             cd ../ml-agents && pip install -e .
-            pip install pre-commit pytest-cov==2.6.1 codacy-coverage==1.3.11
+            pip install pre-commit pytest-cov==2.6.1
             cd ../gym-unity && pip install -e .
 
       - save_cache:
             . venv/bin/activate
             mkdir test-reports
             pytest --cov=mlagents --cov-report xml --junitxml=test-reports/junit.xml -p no:warnings
-            python-codacy-coverage -r coverage.xml
-          name: Check Code Style for ml-agents and gym_unity using black
+          name: Check Code Style using pre-commit
           command: |
             . venv/bin/activate
             pre-commit run --show-diff-on-failure --all-files