Update Node.js to v18 - autoclosed

This MR contains the following updates:

Package	Type	Update	Change
node	image	major	15.14-buster -> 18.11-buster

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Configuration

📅 Schedule: At any time (no schedule defined).

🚦 Automerge: Disabled by config. Please merge this manually once you are satisfied.

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🔕 Ignore: Close this MR and you won't be reminded about this update again.

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