Fix static linking for Bridgeless mode (#43846)

Summary:
Working with gabrieldonadel, we realized that static frameworks of the React-RendererRuntime are not following the proper folder structure.
When a user tries to import `ReactCommon/RCTHost` in the app delegate, for example, the user ends up with an error and they can't find the files.

These changes fixes this by establishing the right folder structure in the static frameworks

## Changelog:
[Internal] - Make sure that React-RuntimeCore and JSErrorHandler are created with the proper structure for static frameworks

Pull Request resolved: https://github.com/facebook/react-native/pull/43846

Test Plan:
Tested locally on an app with 0.74.
Before: it failed to build.
After: it build successfully.

Reviewed By: cortinico

Differential Revision: D55741581

Pulled By: cipolleschi

fbshipit-source-id: 11ac0882d3feea05ef8904d55856ba5704b7a3b8

packages/react-native/ReactCommon/jserrorhandler/React-jserrorhandler.podspec

@@ -41,7 +41,7 @@ Pod::Spec.new do |s|
   s.compiler_flags         = folly_compiler_flags + ' ' + boost_compiler_flags
 
   if ENV['USE_FRAMEWORKS']
-    s.header_mappings_dir     = './'
+    s.header_mappings_dir     = '../'
     s.module_name             = 'React_jserrorhandler'
   end
 

packages/react-native/ReactCommon/react/runtime/React-RuntimeCore.podspec

@@ -42,7 +42,7 @@ Pod::Spec.new do |s|
   s.compiler_flags       = folly_compiler_flags + ' ' + boost_compiler_flags
 
   if ENV['USE_FRAMEWORKS']
-    s.header_mappings_dir     = './'
+    s.header_mappings_dir     = '../../'
     s.module_name             = 'React_RuntimeCore'
   end