Update node Docker tag to v20 - autoclosed

[renovate[bot]]

This PR contains the following updates:

Package	Type	Update	Change	Pending
node	final	major	14-slim -> 20-slim	21-slim

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Release Notes

nodejs/node (node)

### [`v20`](https://togithub.com/nodejs/node/blob/HEAD/CHANGELOG.md#2016-05-06-Version-01214-Maintenance--rvagg) Moved to doc/changelogs/CHANGELOG_V012.md#0.12.14. ### [`v19`](https://togithub.com/nodejs/node/blob/HEAD/CHANGELOG.md#2015-03-19-Version-160-chrisdickinson) Moved to doc/changelogs/CHANGELOG_IOJS.md#1.6.0. ### [`v18`](https://togithub.com/nodejs/node/blob/HEAD/CHANGELOG.md#2015-08-18-Version-310-Fishrock123) Moved to doc/changelogs/CHANGELOG_IOJS.md#3.1.0. ### [`v17`](https://togithub.com/nodejs/node/blob/HEAD/CHANGELOG.md#2015-11-17-Version-510-Stable--Fishrock123) Moved to doc/changelogs/CHANGELOG_V5.md#5.1.0. ### [`v16`](https://togithub.com/nodejs/node/blob/HEAD/CHANGELOG.md#2016-05-06-Version-01214-Maintenance--rvagg) Moved to doc/changelogs/CHANGELOG_V012.md#0.12.14. ### [`v15`](https://togithub.com/nodejs/node/blob/HEAD/CHANGELOG.md#2015-12-23-Version-424-Argon-LTS--jasnell) Moved to doc/changelogs/CHANGELOG_V4.md#4.2.4.

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