chore(deps): update actions/cache action to v4

[renovate[bot]]

This PR contains the following updates:

Package	Type	Update	Change
actions/cache	action	major	v3 -> v4

---

Release Notes

actions/cache (actions/cache)

### [`v4`](https://togithub.com/actions/cache/compare/v3...v4) [Compare Source](https://togithub.com/actions/cache/compare/v3...v4)

---

Configuration

📅 Schedule: Branch creation - "after 10pm every weekday,before 5am every weekday" in timezone Europe/London, 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 has been generated by Mend Renovate. View repository job log here.

[coveralls]

Pull Request Test Coverage Report for Build 7932964735

Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 94.913%

---

Totals
Change from base Build 7932954431:	0.0%
Covered Lines:	358
Relevant Lines:	367

---

💛 - Coveralls