Update nodered/node-red Docker tag to v3.1.5

[renovate[bot]]

This PR contains the following updates:

Package	Update	Change
nodered/node-red	patch	3.1.3-18-minimal -> 3.1.5-18-minimal

---

Release Notes

node-red/node-red-docker (nodered/node-red)

### [`v3.1.5`](https://togithub.com/node-red/node-red-docker/releases/tag/v3.1.5) [Compare Source](https://togithub.com/node-red/node-red-docker/compare/v3.1.4...v3.1.5) #### What's Changed - 🚀 Update to Node-RED 3.1.5 release by [@​knolleary](https://togithub.com/knolleary) in [https://github.com/node-red/node-red-docker/pull/410](https://togithub.com/node-red/node-red-docker/pull/410) **Full Changelog**: https://github.com/node-red/node-red-docker/compare/v3.1.4...v3.1.5 ### [`v3.1.4`](https://togithub.com/node-red/node-red-docker/releases/tag/v3.1.4) [Compare Source](https://togithub.com/node-red/node-red-docker/compare/v3.1.3...v3.1.4) ##### What's Changed - 📝Fix Docker image tag and Node version mismatch in README.md by [@​takuya-o](https://togithub.com/takuya-o) in [https://github.com/node-red/node-red-docker/pull/401](https://togithub.com/node-red/node-red-docker/pull/401) - Update healthcheck.js by [@​hardillb](https://togithub.com/hardillb) in [https://github.com/node-red/node-red-docker/pull/405](https://togithub.com/node-red/node-red-docker/pull/405) - 🚀 Update to Node-RED 3.1.4 release by [@​knolleary](https://togithub.com/knolleary) in [https://github.com/node-red/node-red-docker/pull/409](https://togithub.com/node-red/node-red-docker/pull/409) ##### New Contributors - [@​takuya-o](https://togithub.com/takuya-o) made their first contribution in [https://github.com/node-red/node-red-docker/pull/401](https://togithub.com/node-red/node-red-docker/pull/401) **Full Changelog**: https://github.com/node-red/node-red-docker/compare/v3.1.3...v3.1.4

---

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 Mend Renovate. View repository job log here.