fix: Field allways passes a undefined className to custom component

[myNameIsDu]

Close #3883

The current issue stems from a specific PR, The original issue can be found here

There are some explanations

1. PR is a little unusual, because the className prop was already included by props, and this style of writing (extracting it from props and then passing it into children's props alone) will cause there's always a className in children's props
2. The original issue is confusing, because the className is already passed, except that there's no declaration.

Then there are three revisions in this PR

1. Delete extracted className, but keep the type declaration
2. Add test cases
3. Fix the wrong usage of cases function in the test cases before by the way

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🦋 Changeset detected

Latest commit: fb09a09

The changes in this PR will be included in the next version bump.

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formik	Patch
formik-native	Patch

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Name	Status	Preview	Comments	Updated (UTC)
formik-docs	✅ Ready (Inspect)	Visit Preview	💬 Add feedback	Sep 14, 2023 8:21am

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[colin-oos]

Any update on this?

[colin-oos]

Bumping this again. This really needs to get merged. Currently you are not able to style custom components because className on the custom component is always undefined.