feat(docker-image)!: Update ghcr.io/mendhak/http-https-echo Docker tag to v31 - autoclosed

[repo-duster[bot]]

This PR contains the following updates:

Package	Update	Change
ghcr.io/mendhak/http-https-echo	major	30 -> 31

---

Release Notes

mendhak/docker-http-https-echo (ghcr.io/mendhak/http-https-echo)

### [`v31`](https://togithub.com/mendhak/docker-http-https-echo/blob/HEAD/CHANGELOG.md#Version-31---2023-12-03) [Compare Source](https://togithub.com/mendhak/docker-http-https-echo/compare/30...31) - Use `PROMETHEUS_ENABLED` which enables a Prometheus metrics endpoint at /metrics

---

Configuration

📅 Schedule: Branch creation - At any time (no schedule defined), 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 Renovate Bot.