style: refactor async trait with async-fn-in-trait and return-position-impl-trait-in-trait

[BugenZhao]

These features are still unstable but not considered to be "incomplete" now! We can use them to simplify the async trait interfaces.

Already done:

• refactor: Use async function in trait rather GAT to simplify code #8422
• refactor(connector): avoid using macro in parser #10120
• refactor(frontend): simplify interfaces of pgwire #10406
• refactor(storage): simplify associated type in state store trait #10756
• feat(log-store): refine log store trait and add update vnode bitmap in reader #11959
• refactor(sink): refine sink trait and macro #12478

By searching the codebase with type .+ = impl .*Future, I find that the storage module is the most significant and valuable part to refactor. cc @wenym1

[github-actions]

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