Update node Docker tag to v20

[renovate[bot]]

This PR contains the following updates:

Package	Type	Update	Change
node	container	major	14.4 -> 20.5

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Release Notes

nodejs/node (node)

v15.11

Moved to doc/changelogs/CHANGELOG_V012.md#0.12.8.

v15.1

Moved to doc/changelogs/CHANGELOG_V012.md#0.12.8.

v14.12

Moved to doc/changelogs/CHANGELOG_V010.md#0.10.35.

v14.10

Moved to doc/changelogs/CHANGELOG_V010.md#0.10.33.

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Configuration

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