chore(release): 2.6.7-rc.4

## [2.6.7-rc.4](https://github.com/AnotherStranger/docker-borg-backup/compare/v2.6.7-rc.3...v2.6.7-rc.4) (2025-02-27)

### Code Refactoring

* **deps:** update sigstore/cosign-installer action to v3.8.1 ([70d7af2b](https://github.com/AnotherStranger/docker-borg-backup/commit/70d7af2b0b3c97c48d93d241d543f256ff677563))