Add information about nested stack and headerShown being unsupported for formSheet on Android

[kligarski]

Description

Add information about headerShown prop and nested stack in a presentation: 'formSheet' screens being currently unsupported on Android.

Thanks to @ljukas for pointing out the missing docs.

[kligarski]

@kkafar

[netlify[bot]]

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[MrFunctor]

Hey folks! Is there any reason why this PR hasn't been merged? It contains useful information that otherwise needs to be looked up in issues.

[kligarski]

@satya164