GH Action test workflow: install PythonQwt from repo for develop branch test

Author: PierreRaybaut

.github/workflows/test_pyqt5.yml

@@ -39,11 +39,13 @@ jobs:
         python setup.py build_ext --inplace
         pip install .[test]
         if [ "${{ github.ref_name }}" = "develop" ]; then
-           pip uninstall -y guidata
+           pip uninstall -y guidata PythonQwt
            cd ..
            git clone --depth 1 --branch develop https://github.com/PlotPyStack/guidata.git
-           cd PlotPy
+           git clone --depth 1 https://github.com/PlotPyStack/PythonQwt.git
            pip install -e ../guidata
+           pip install -e ../PythonQwt
+           cd PlotPy
         fi
     - name: Lint with Ruff
       run: ruff check --output-format=github plotpy