3.12.0

This minor release includes initial support for Fabric architecture 🎉

To learn about what we've achieved so far check out our Introducing Fabric to React Native Screens blog post.

Changes:

• Add Fabric example app (#1261) by @Ubax
• Publish Fabric and classic architecture release (#1308) by @Ubax
• Add test build Fabric workflows (#1321) by @kacperkapusciak and @Ubax
• Fix headerTitle & title props (#1320) by @kacperkapusciak
• Remove enableFabric requirement (#1319) by @Ubax
• Remove additional config steps required when running Fabric version on Android (#1322) by @kmagiera
• Fix Android props on Paper (#1325) by @Ubax
• Reword sentences in Fabric section (#1327) by @kacperkapusciak
• Cleanup build process for pre-codegen versions of react-native (#1328) by @kmagiera