chore(deps): update node.js to v21 - autoclosed

This MR contains the following updates:

Package	Type	Update	Change
node	image	major	20-alpine -> 21-alpine
node	stage	major	20-alpine -> 21-alpine

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Release Notes

nodejs/node (node)

v21

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

nodejs/node (node)

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