docs: bump 'actions/checkout' to latest released version 7

[deining]

This PR bumps actions/checkout to latest released version 7 in the documentation.

[astrobot-houston]

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Tracked Files

File	Note
en/guides/deploy/aws.mdx	Source changed, localizations will be marked as outdated.
en/guides/deploy/deno.mdx	Source changed, localizations will be marked as outdated.
en/guides/deploy/github.mdx	Source changed, localizations will be marked as outdated.

Warnings reference

Icon	Description
🔄️	The source for this localization has been updated since the creation of this pull request, make sure all changes in the source have been applied.

[github-actions]

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