fix(deps): update dependency @actions/cache to v6

[renovate]

This PR contains the following updates:

Package	Change	Age	Confidence
@actions/cache (source)	5.0.5 → 6.0.0

---

Release Notes

actions/toolkit (@​actions/cache)

v6.0.0

• Breaking change: Package is now ESM-only
  • CommonJS consumers must use dynamic import() instead of require()

---

Configuration

📅 Schedule: Branch creation - "every 2 day" (UTC), Automerge - At any time (no schedule defined).

🚦 Automerge: Disabled by config. Please merge this manually once you are satisfied.

♻ Rebasing: Whenever PR becomes conflicted, or you tick the rebase/retry checkbox.

🔕 Ignore: Close this PR and you won't be reminded about this update again.

---

• If you want to rebase/retry this PR, check this box

---

This PR was generated by Mend Renovate. View the repository job log.