Bump node-red from 3.1.7 to 3.1.8

Bumps [node-red](https://github.com/node-red/node-red) from 3.1.7 to 3.1.8.
- [Release notes](https://github.com/node-red/node-red/releases)
- [Changelog](https://github.com/node-red/node-red/blob/master/CHANGELOG.md)
- [Commits](node-red/node-red@3.1.7...3.1.8)

---
updated-dependencies:
- dependency-name: node-red
  dependency-type: direct:development
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>