Update build.gradle with namespace

[Joatin]

This commit adds support for RN 0.73 android builds

Summary

Add namespace to android section of build.gradle, this is a requirement for Gradle 8 which is the default for RN 0.73+. It's wrapped in a version check for backwards compatability.

Motivation

Android won't build without it

Testing

• [ x] I tested this manually
• [ ] I added automated tests

Documentation

Select one:

• [ ] I have added relevant documentation for my changes.
• [ x] This PR does not result in any developer-facing changes.

[CLAassistant]

All committers have signed the CLA.