update upload-artifact action

Author: carloalbertobarbano

.github/workflows/tests_full.yml

@@ -28,7 +28,7 @@ jobs:
         run: python setup.py bdist_wheel
 
       - name: Upload Python wheel
-        uses: actions/upload-artifact@v2
+        uses: actions/upload-artifact@v4
         with:
           name: Python wheel
           path: ${{github.workspace}}/dist/torchstain-*.whl

.github/workflows/tests_quick.yml

@@ -25,7 +25,7 @@ jobs:
         run: python setup.py bdist_wheel
 
       - name: Upload Python wheel
-        uses: actions/upload-artifact@v2
+        uses: actions/upload-artifact@v4
         with:
           name: Python wheel
           path: ${{github.workspace}}/dist/torchstain-*.whl