Update more actions to use nodejs20 runtime and also update the docs for
checkout action usage.
similar to:
- #27836
- #27096
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Signed-off-by: Rui Chen <rui@chenrui.dev>
- Remove actions name where command is descriptive enough
- Use kebab-case instead of snake-case for step names
- Use shorter job names because to make PR checks more readable
- Remove duplicate `checks-backend`
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Co-authored-by: Yarden Shoham <git@yardenshoham.com>
