Bump actions/upload-artifact from 4 to 6

Bumps [actions/upload-artifact](https://github.com/actions/upload-artifact) from 4 to 6.
- [Release notes](https://github.com/actions/upload-artifact/releases)
- [Commits](https://github.com/actions/upload-artifact/compare/v4...v6)

---
updated-dependencies:
- dependency-name: actions/upload-artifact
  dependency-version: '6'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

.github/workflows/release.yml

@@ -51,14 +51,14 @@ jobs:
                 echo $(xcodebuild -showsdks)
                 ls -alh
             - name: Upload unix artifacts
-              uses: actions/upload-artifact@v4
+              uses: actions/upload-artifact@v6
               if: contains(matrix.os, 'ubuntu')
               with:
                 name: unix-binaries
                 path: |
                     ${{ github.event.repository.name }}-${{github.ref_name}}-*.tar.gz
             - name: Upload macos artifacts
-              uses: actions/upload-artifact@v4
+              uses: actions/upload-artifact@v6
               if: contains(matrix.os, 'macos')
               with:
                 name: macos-binaries