Revert "Merge pull request #534 from keisuke-umezawa/feature/introduce-python-coverage"

This reverts commit 0f4fc37fca, reversing
changes made to a7cf1d8f68.

.github/workflows/python-tests.yml

@@ -45,8 +45,7 @@ jobs:
         # python_tests requires optuna>=3.0.0 since it imports FloatDistribution
         run: |
           python -m pip install --progress-bar off --upgrade pip setuptools
-          pip install --progress-bar off .[optional]
-          pip install --progress-bar off .[test]
+          pip install streamlit boto3 moto[s3] pytest
           pip install --progress-bar off "optuna>=3.0.0"
           pip install --progress-bar off .
       - run: pytest python_tests
@@ -62,8 +61,7 @@ jobs:
       - name: Install dependencies
         run: |
           python -m pip install --progress-bar off --upgrade pip setuptools
-          pip install --progress-bar off .[optional]
-          pip install --progress-bar off .[test]
+          pip install streamlit boto3 moto[s3] pytest
           pip install --progress-bar off .
           python -m pip install --progress-bar off --upgrade git+https://github.com/optuna/optuna.git
       - run: pytest python_tests