Update Docker version docs to reflect recent default changes

[JoeMitchellJones]

Changes the current Docker version documentation to reflect Docker 28 as the new default, and the addition of Docker 29

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Description

What did you change?
Modified the Docker versions in guides to reflect the new available versions and defaults after the 28 rollout

Reasons

Why did you make these changes? What problem does this solve?
They are currently inaccurate, stating the default as 27 and other details such as the delayed 28 release which has now happened

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[JoeMitchellJones]

Confirmed that none of the linting errors are related to the changes made in this PR