Trying python3 -m pip install to install scikit-learn

.github/workflows/ci.yaml

@@ -24,7 +24,7 @@ jobs:
         run: |
           python -m pip install --upgrade pip
           pip install -e $GITHUB_WORKSPACE
-          pip install -r requirements.txt
+          python3 -m pip install -r requirements.txt
       - name: Unit tests
         run: |
           python -m tests.grid_tests