Extend shared Renovate preset

[NWarila]

Summary

• Extends the shared UBI9 Renovate preset before config:recommended.
• Removes the local PR concurrency override so the shared fan-out caps govern.
• Removes the local Docker golang package rule so the shared Go-FIPS boundary governs.
• Leaves stack-local managers and rules intact.

Validation

• npx --yes renovate-config-validator .github/renovate.json5
• rg -n "certificate-identity" .github/workflows/publish-image.yaml docs/reference/slsa-l3-provenance.md