Fix ARGB images save when using WebP.

Upload artifacts.

.github/workflows/eepp-linux-build-check.yml

@@ -39,3 +39,20 @@ jobs:
       run: |
         cd bin/unit_tests
         xvfb-run ./eepp-unit_tests
+    - name: Upload test artifacts if folder exists
+      if: always()
+      run: |
+        if [ -d bin/unit_tests/output ]; then
+          echo "Artifact folder exists (bin/unit_tests/output), uploading..."
+          exit 0
+        else
+          echo "No artifact folder (bin/unit_tests/output), tests passed, skipping upload."
+          exit 0
+        fi
+      id: upload-check
+    - name: Upload artifacts
+      if: always() && steps.upload-check.outputs.result == '0' && exists('bin/unit_tests/output')
+      uses: actions/upload-artifact@v4
+      with:
+        name: linux-test-output
+        path: bin/unit_tests/output/*