feat: upload artifacts from visual comparison for inspection

It allows evaluating whether the visual differences are acceptable

.github/workflows/main.yml

@@ -52,3 +52,11 @@ jobs:
         run: bundle exec rake compile
       - name: run the tests
         run: bundle exec rspec
+        id: test
+      - name: upload test artifacts
+        uses: actions/upload-artifact@v4
+        with:
+          name: 'visual-matching-results'
+          path: 'tmp/reference-image-matches'
+          if-no-files-found: ignore
+        if: success() || steps.test.conclusion == 'failure'