Update Node.js to v21 - autoclosed

This MR contains the following updates:

Package	Type	Update	Change
node	final	major	20 -> 21

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Release Notes

nodejs/node (node)

v21

Moved to doc/changelogs/CHANGELOG_V4.md#4.2.6.

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Configuration

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

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