chore(deps): update node.js to v21

[renovate[bot]]

This PR contains the following updates:

Package	Type	Update	Change
node	final	major	20-alpine -> 21-alpine

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Release Notes

nodejs/node (node)

### [`v21`](https://togithub.com/nodejs/node/blob/HEAD/CHANGELOG.md#2016-01-21-Version-426-Argon-LTS--TheAlphaNerd) Moved to doc/changelogs/CHANGELOG_V4.md#4.2.6.

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