docs: Updated github action versions

[Chriztiaan]

The doc deploy action has started failing due to a deprecated action no longer working - the two actions I have bumped wrap that action.
I have updated to the versions recommended in the upload-pages-artifact v3 release here: https://github.com/actions/upload-pages-artifact/releases

Example build failure: https://github.com/powersync-ja/powersync-js/actions/runs/13054794562

Writeup of deprecation: https://github.blog/changelog/2024-04-16-deprecation-notice-v3-of-the-artifact-actions/

[changeset-bot]

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