Reach public modules through umbrellas in RN-Tester and popup-menu-android C++ (#59222)

Summary:
Pull Request resolved: #59222

Two C++ files built into RN-Tester include public React Native headers directly instead of through their module umbrella, which is an `#error` under `RN_STRICT_API`:

- `rn-tester/NativeCxxModuleExample/NativeCxxModuleExample.cpp`,
- `react/debug/react_native_assert.h`,
- The checked-in codegen output of `react-native/popup-menu-android` (`Props.cpp`) included `react/renderer/core/PropsParserContext.h` and `propsConversions.h`.

No behavior change; this prepares RN-Tester to build with `RN_STRICT_API` by default.

Changelog: [Internal]

___

landed-with-radar-review

Differential Revision: D126328619

fbshipit-source-id: fcc301252afe87e108a78ccc5565ddc6b7bfd294

Author: coado

packages/react-native-popup-menu-android/android/src/main/jni/react/renderer/components/ReactPopupMenuAndroidSpecs/Props.cpp

@@ -9,8 +9,7 @@
  */
 
 #include "Props.h"
-#include <react/renderer/core/PropsParserContext.h>
-#include <react/renderer/core/propsConversions.h>
+#include <React/RendererCore.h>
 
 namespace facebook::react {
 

packages/rn-tester/NativeCxxModuleExample/NativeCxxModuleExample.cpp

@@ -6,8 +6,8 @@
  */
 
 #include "NativeCxxModuleExample.h"
-#include <react/bridging/ArrayBuffer.h>
-#include <react/debug/react_native_assert.h>
+#include <React/Bridging.h>
+#include <React/Debug.h>
 #include <iomanip>
 #include <numeric>
 #include <ostream>