[RNMobile] Add setMinHeightToMaxHeight prop to bottom sheet

[jhnstn]

Description

This adds the ability to set the minHeight equal to the maxHeight of the BottomSheet component. This is useful when trying to render dynamic content within the bottom sheet. The current need is for Inserter Block Search project.

How has this been tested?

Note: The Inserter Block Search is currently behind the __DEV__ flag.

1. Start the Mobile Gutenberg demo app
2. Open the mobile editor
3. Open the block inserter menu
4. Press on "Search Blocks"
5. Enter a search query that returns few results e.g. img
6. The bottom sheet height should not change.

Screenshots

Before:

Android	iPhone

After:

Android	iPhone

Types of changes

New feature (non-breaking change which adds functionality)

• Adds a setMinHeightToMaxHeight prop to the BottomSheet component. When true the bottom sheet will have a static height equal to the max height. example:

<BottomSheet setMinHeightToMaxHeight={ true } > 

Checklist:

• My code is tested.
• My code follows the WordPress code style.
• My code follows the accessibility standards.
• I've tested my changes with keyboard and screen readers.
• My code has proper inline documentation.
• I've included developer documentation if appropriate.
• I've updated all React Native files affected by any refactorings/renamings in this PR.

[github-actions]

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[AmandaRiu]

@jhnstn Changes look good. Tested on an Android emulator and iOS simulator in portrait and landscape mode. Unrelated to this PR I noticed that in landscape mode on Android, the text entry goes into full screen mode. I wonder if there is a way to prevent this with React Native so the results always stay visible as the user it typing:

Screen.Recording.2021-03-22.at.4.54.11.PM.mov

PR is approved and ready for merge. The gutenberg-mobile PR just needs to be updated with the merge commit and then that one will be ready for final review as well. Since this is a feature available in devMode only, then the gutenberg-mobile PR doesn't require being merged and could just be closed.