Bump actions/upload-artifact from 2 to 3

Bumps [actions/upload-artifact](https://github.com/actions/upload-artifact) from 2 to 3.
- [Release notes](https://github.com/actions/upload-artifact/releases)
- [Commits](https://github.com/actions/upload-artifact/compare/v2...v3)

---
updated-dependencies:
- dependency-name: actions/upload-artifact
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>

.github/workflows/assembleFlavors.yml

@@ -23,7 +23,7 @@ jobs:
             echo "org.gradle.jvmargs=-Xmx2g -XX:MaxMetaspaceSize=512m -XX:+HeapDumpOnOutOfMemoryError" >> gradle.properties
             ./gradlew assemble${{ matrix.flavor }}
       -   name: Archive apk
-          uses: actions/upload-artifact@v2
+          uses: actions/upload-artifact@v3
           if: ${{ always() }}
           with:
               name: Nextcloud-APK