Don't use the internal native_modules.rb script yet (facebook#35531)

Summary:
Revert the template `Podfile` to using `react-native-community/cli-platform-ios/native_modules`. The new internal script currently has a hard-coded path to `react-native-community/cli-platform-ios` which may not work in monorepos. The path in the `Podfile` is also hard-coded, but this is a file that the user has access to and can fix themselves if necessary.

## Changelog

[iOS] [Fixed] - Don't use the internal `native_modules.rb` script yet, as it hides a hard-coded path

Pull Request resolved: facebook#35531

Test Plan: n/a

Reviewed By: rshest

Differential Revision: D41682119

Pulled By: cortinico

fbshipit-source-id: 1822fcd20a794dc9df6e8d6f36615e90b42c1a94

template/ios/Podfile

@@ -1,5 +1,5 @@
 require_relative '../node_modules/react-native/scripts/react_native_pods'
-require_relative '../node_modules/react-native/scripts/native_modules'
+require_relative '../node_modules/@react-native-community/cli-platform-ios/native_modules'
 
 platform :ios, min_ios_version_supported
 prepare_react_native_project!