RN project wide Kotlin version

[dulmandakh]

Summary

This PR sets project wide Kotlin version to 1.4.21, supported in Buck https://github.com/facebook/buck/tree/dev/third-party/java/kotlin.

We had to specify version for both kotlin-dsl and kotlin('jvm') plugins to remove version mismatch warnings in react-native-gradle-plugin. Also I expect more Kotlin code in RN, so instead of specifying version for each sub-project it's better to have project wide setting.

We don't need to load Kotlin in react-native-gradle-plugin because Kotlin is available RN project wide.

Changelog

[Internal] [Changed] - Project wide Kotlin version set to 1.4.21

Test Plan

Everything works as expected, no visible change for developers.

[dulmandakh]

@ShikaSD please review and merge

[analysis-bot]

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

Base commit: 286fac5

[analysis-bot]

Platform	Engine	Arch	Size (bytes)	Diff
android	hermes	arm64-v8a	9,239,992	+0
android	hermes	armeabi-v7a	8,749,684	+0
android	hermes	x86	9,702,602	+0
android	hermes	x86_64	9,667,479	+0
android	jsc	arm64-v8a	10,885,297	+0
android	jsc	armeabi-v7a	9,786,263	+0
android	jsc	x86	10,943,305	+0
android	jsc	x86_64	11,549,705	+0

Base commit: 286fac5

[facebook-github-bot]

@ShikaSD has imported this pull request. If you are a Facebook employee, you can view this diff on Phabricator.

[facebook-github-bot]

@ShikaSD merged this pull request in 9a5e226.