Setup Gradle Wrapper inside packages/react-native-gradle-plugin/

[cortinico]

Summary:
This diff is setting up the Gradle wrapper inside packages/react-native-gradle-plugin/.
Currently the ./gradlew file is missing so it's not possible to cd inside the project and build it from
there (also opening that folder inside the IDE will trigger the creation of the files I added here).

This diff is fixing. The files have been generated with the command:

gw -p packages/react-native-gradle-plugin wrapper --gradle-version 7.0.2 --distribution-type=all

Changelog:
[Internal] [Added] - Setup Gradle Wrapper inside packages/react-native-gradle-plugin/

Differential Revision: D30730145

[facebook-github-bot]

This pull request was exported from Phabricator. Differential Revision: D30730145

[pull-bot]

	Messages
📖	📋 Missing Changelog - Can you add a Changelog? To do so, add a "## Changelog" section to your PR description. A changelog entry has the following format: [CATEGORY] [TYPE] - Message. Details CATEGORY may be: General iOS Android JavaScript Internal (for changes that do not need to be called out in the release notes) TYPE may be: Added, for new features. Changed, for changes in existing functionality. Deprecated, for soon-to-be removed features. Removed, for now removed features. Fixed, for any bug fixes. Security, in case of vulnerabilities. MESSAGE may answer "what and why" on a feature level. Use this to briefly tell React Native users about notable changes.
📖	📋 Missing Test Plan - Can you add a Test Plan? To do so, add a "## Test Plan" section to your PR description. A Test Plan lets us know how these changes were tested.
📖	📋 Missing Summary - Can you add a Summary? To do so, add a "## Summary" section to your PR description. This is a good place to explain the motivation for making this change.

Generated by 🚫 dangerJS against ad9d93e

[analysis-bot]

Platform	Engine	Arch	Size (bytes)	Diff
ios	-	universal	n/a	--

Base commit: b1120c6

[analysis-bot]

Platform	Engine	Arch	Size (bytes)	Diff
android	hermes	arm64-v8a	8,964,703	+0
android	hermes	armeabi-v7a	8,496,854	+0
android	hermes	x86	9,390,933	+0
android	hermes	x86_64	9,358,391	+0
android	jsc	arm64-v8a	10,628,158	+0
android	jsc	armeabi-v7a	9,549,495	+0
android	jsc	x86	10,641,388	+0
android	jsc	x86_64	11,252,563	+0

Base commit: b1120c6

[facebook-github-bot]

This pull request has been merged in 040f548.