Fix to Python 3.8 being deprecated for Sphinx-Build

.github/workflows/build_and_test.yml

@@ -32,16 +32,15 @@ jobs:
       env:
         PY_VER: ${{ matrix.python-version }}
       run: |
-        if [[ "$PY_VER" = "3.7" ]]; then pytest --cov=gym_electric_motor tests/; else pytest; fi
-        if [[ "$PY_VER" = "3.7" ]]; then bash <(curl -s https://codecov.io/bash); fi # code coverage report upload
+        pytest
   build-doc:
     runs-on: ubuntu-latest
     steps:
     - uses: actions/checkout@v3
     - name: Build Sphinx documentation
-      uses: ammaraskar/sphinx-action@master
+      uses: nicholasphair/sphinx-action@7.0.0
       with:
-        pre-build-command: "python -m pip install sphinx m2r2 sphinx_rtd_theme==1.3.0 && python -m pip install -r requirements.txt & python -m pip install ."
+        pre-build-command: "python -m pip install sphinx m2r2 sphinx_rtd_theme==1.3.0 && python -m pip install -r requirements.txt && python -m pip install ."
         docs-folder: "docs/"
     # Publish built docs to gh-pages branch.
     # ===============================