Merge pull request #463 from blowekamp/fix_gha_test_pypi

Enable upgrade to SimpleITK version on test pypi

.github/workflows/scheduled_or_manual.yml

@@ -70,7 +70,7 @@ jobs:
         python -m pip install -r requirements_dev.txt
     - name: Install SimpleITK from test PyPi from manually launched workflow
       if: ${{ inputs.testPyPi }}
-      run: pip install --index-url https://test.pypi.org/simple/ --extra-index-url https://pypi.org/simple SimpleITK
+      run: pip install --upgrade --index-url https://test.pypi.org/simple/ SimpleITK
     - name: Download data
       if: steps.cache.outputs.cache-hit != 'true'
       run: python Utilities/downloaddata.py Data/ Data/manifest.json