fix(node): increase required node >=18.5

[Rotzbua]

• Bugfix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)

Proposed changes

Test statement can be simplified by increasing the required minor version. Earlier node version seem buggy.

Checklist

• I have read the contribution guidelines
• For non-bugfix PRs, I have discussed this change on the forum/slack team.
• I have run npm run test to verify the unit tests pass
• I have added suitable unit tests to cover the new/changed functionality

Reference

#4687

[knolleary]

We'll also need to update packages/node_modules/node-red/package.json to match