chore(deps): update Dockerfile node.js to v21

[renovate[bot]]

This PR contains the following updates:

Package	Type	Update	Change
node	final	major	20-alpine3.17 -> 21-alpine3.17
node	stage	major	20-alpine3.17 -> 21-alpine3.17

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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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[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Comparison is base (4a32195) 81.34% compared to head (7b2a59f) 81.34%.

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #883 +/- ## ======================================= Coverage 81.34% 81.34% ======================================= Files 16 16 Lines 1731 1731 Branches 411 411 ======================================= Hits 1408 1408 Misses 309 309 Partials 14 14 ```

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