Update actions/upload-artifact action to v7 (#353)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

.github/workflows/publish.yml

@@ -30,7 +30,7 @@ jobs:
       - name: Execute Gradle build
         run: ./gradlew createLocalM2 -PPGP_KEY="${{secrets.PGP_KEY}}" -PPGP_PAS="${{secrets.PGP_PAS}}"
 
-      - uses: actions/upload-artifact@v6
+      - uses: actions/upload-artifact@v7
         with:
           name: m2
           path: build/m2