ci: upgrade flint to v0.4.0 and adopt renovate-deps lint

- Update flint from v0.2.0 to v0.4.0 (SHA-pinned)
- Use flint Renovate preset for custom managers
- Remove manual URL remap step from lint workflow (now in flint)
- Add lint:renovate-deps task and regenerate tracked deps
Signed-off-by: Gregor Zeitlinger <gregor.zeitlinger@grafana.com>

Author: zeitlinger