Try exporting python to path and use that

.github/workflows/pytest.yml

@@ -95,7 +95,6 @@ jobs:
       if: matrix.kind == 'dist'
       run: |
         python -m pip install --upgrade pip
-        sudo apt-get update
         python setup.py sdist
         last_dist=$(ls -t dist/ConfigSpace-*.tar.gz | head -n 1)
         python -m pip install $last_dist[test]
@@ -109,15 +108,13 @@ jobs:
       timeout-minutes: 45
       run: |
         if [[ ${{ matrix.kind }} == 'conda' ]]; then
-          PYTHON=$CONDA/envs/testenv/bin/python3
-        else
-          PYTHON=$(which python)
+          export PATH="$CONDA/envs/testenv/bin:$PATH"
         fi
 
         if [ ${{ matrix.code-cov }} ]; then
-          $PYTHON -m pytest ${{ env.pytest-args }} ${{ env.code-cov-args }} test
+          pytest ${{ env.pytest-args }} ${{ env.code-cov-args }} test
         else
-          $PYTHON -m pytest ${{ env.pytest-args }} test
+          pytest ${{ env.pytest-args }} test
         fi
 
     - name: Check for files left behind by test