types(defineProps): remove optional properties from type

[pikax]

fixes #6420

I haven't tested this on an actual repo.

When we use defineProps<{ a?:string}> it will create a type { a?: string } which is not correct for the vue props context, since if a property is declared the key will always be present, a more accurate representation of the type is { a: string | undefined }, this PR does that.

[netlify[bot]]

❌ Deploy Preview for vuejs-coverage failed.

Name	Link
🔨 Latest commit	43065b51032cf22c6cd4c9c274113a42ba561b9c
🔍 Latest deploy log	https://app.netlify.com/sites/vuejs-coverage/deploys/62efd0f4eb1fea0009152167

[Justineo]

Maybe related: https://github.com/vuejs/core/pull/6244

[github-actions[bot]]

Size Report

Bundles

File	Size	Gzip	Brotli
runtime-dom.global.prod.js	86.4 kB	32.9 kB	29.6 kB
vue.global.prod.js	132 kB	49.6 kB	44.5 kB

Usages

Name	Size	Gzip	Brotli
createApp	48 kB	18.9 kB	17.3 kB
createSSRApp	51.1 kB	20.1 kB	18.4 kB
defineCustomElement	50.3 kB	19.7 kB	17.9 kB
overall	61.3 kB	23.7 kB	21.6 kB