Actions: push to SourceForge only when new commits exists

.github/workflows/build-nightly.yml

@@ -144,12 +144,14 @@ jobs:
          token: ${{ secrets.GH_PAT }}
          repo: distribution-nightly
      - name: Set up SSH sourceforge
+       if: env.new_commits == 'true'
        run: |
          mkdir -p ~/.ssh
          echo "${{ secrets.SF_SSH_KEY }}" > ~/.ssh/id_ed25519
          chmod 600 ~/.ssh/id_ed25519
          ssh-keyscan frs.sourceforge.net >> ~/.ssh/known_hosts
      - name: Upload files sourceforge
+       if: env.new_commits == 'true'
        run: |
          FILES=$(find . -type f \( -name "*.tar" -o -name "*.img.gz" -o -name "*.sha256" \))
          for FILE in $FILES; do