Change github action version

Author: monikakonieczna

.github/workflows/run-tests-by-group.yml

@@ -50,7 +50,7 @@ jobs:
           CI: true
 
       - name: Upload test results
-        uses: actions/upload-artifact@v2
+        uses: actions/upload-artifact@v4
         with:
           name: test-results
           path: junit.xml