Add conditional upload step for test results in workflow

.gitea/workflows/run_tests.yml

@@ -30,4 +30,10 @@ jobs:
       with:
         name: pytest-results
         path: pytest-results.xml
-        retention-days: 5
+        retention-days: 5
+
+    - uses: actions/upload-artifact@v4  # upload test results
+      if: ${{ !cancelled() }}           # run this step even if previous step failed
+      with:
+        name: pytest-results
+        path: pytest-results.xml