fix(types): add typings for async components state handling

[ivansieder]

What kind of change does this PR introduce? (check at least one)

• Bugfix
• Feature
• Code style update
• Refactor
• Build-related changes
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Does this PR introduce a breaking change? (check one)

• Yes
• No

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• New/updated tests are included

If adding a new feature, the PR's description includes:

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Other information:

[KaelWD]

Possible duplicate of #8438?

[ivansieder]

I guess it is, thanks @KaelWD. Been actually looking through the open RRs, but seems like I've overlooked it!

[KaelWD]

Yours might be better though, and has a test which usually helps. Haven't had a good look at either but it seems like #8438 only applies to options.components, not Vue.component.