build(deps): update actions/upload-artifact to v7 (#3)

Approved after native, Uno, ESP32, Pico, and packaging checks passed.

Author: dependabot[bot]

.github/workflows/ci.yml

@@ -42,7 +42,7 @@ jobs:
         with:
           python-version: "3.14"
       - run: python tools/build_release.py
-      - uses: actions/upload-artifact@v6
+      - uses: actions/upload-artifact@v7
         with:
           name: ArduinoPatterns
           path: dist/ArduinoPatterns-*.zip