[iOS] enable new architecture for react-native

This commit enables `Fabric` and `Hermes` for `iOS` and in my initial tests the app seemed to behave well.
We can't do this for Android yet because the blur view implementation is not ported to `Fabric` properly.
needed for #18138

Please check builds from this PR to see if you notice any performance improvements or degradation.

Please smoke test the iOS builds to see if there are any crashes.

- iOS

status: ready

ios/Podfile

@@ -48,7 +48,7 @@ abstract_target 'Status' do
  use_react_native!(
  :path => config[:reactNativePath],
  :fabric_enabled => flags[:fabric_enabled],
- :hermes_enabled => false,
+ :hermes_enabled => true,
  # An absolute path to your application root.
  :app_path => "#{Pod::Config.instance.installation_root}/.."
  )