Remove Kotlin requirement from react-native

[lemnik]

Goal

Avoid version conflicts between the react-native project, the Android Gradle Plugin and Kotlin Gradle Plugin

Design

Replaced the Kotlin layer in the react-native project with plain Java, which has no strict Gradle plugin dependency. Using bounded or wildcard dependencies results in older versions of Gradle being unable to run the build because the Kotlin Gradle Plugin used will be too new. Relying on other build scripts to import their expected version of the Kotlin plugin doesn't work if no other modules require Kotlin.

The react-native module has very little real logic (most is in bugsnag-plugin-react-native), which makes this a relatively lightweight change.

Testing

Relied on existing tests

[github-actions]

@bugsnag/browser bundle size diff

	Minified	Minfied + Gzipped
Before	42.48 kB	12.99 kB
After	42.48 kB	12.99 kB
±	No change	No change

code coverage diff

Coverage values did not change👌.

Total:

Lines	Branches	Functions	Statements
0%(+0%)	0%(+0%)	0%(+0%)	0%(+0%)

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