Append -Wpedantic only for example apps (#6250)

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## Summary

This PR temporarily fixes
#6234
by making the problematic `-Wpedantic` flag to be applied only in
Reanimated example apps so that we can monitor the soundness of the code
on the CI.

`-Wpedantic` flag was introduced in #6157 and released in 3.13.0.

## Test plan

Check if the CI is green.

packages/react-native-reanimated/android/CMakeLists.txt

@@ -15,14 +15,14 @@ add_compile_options(${folly_FLAGS})
 
 string(APPEND CMAKE_CXX_FLAGS " -DREACT_NATIVE_MINOR_VERSION=${REACT_NATIVE_MINOR_VERSION} -DREANIMATED_VERSION=${REANIMATED_VERSION} -DHERMES_ENABLE_DEBUGGER=${HERMES_ENABLE_DEBUGGER}")
 
-string(APPEND CMAKE_CXX_FLAGS " -fexceptions -fno-omit-frame-pointer -frtti -fstack-protector-all -std=c++${CMAKE_CXX_STANDARD} -Wall -Wpedantic -Werror")
+string(APPEND CMAKE_CXX_FLAGS " -fexceptions -fno-omit-frame-pointer -frtti -fstack-protector-all -std=c++${CMAKE_CXX_STANDARD} -Wall -Werror")
 
 if(${IS_NEW_ARCHITECTURE_ENABLED})
     string(APPEND CMAKE_CXX_FLAGS " -DRCT_NEW_ARCH_ENABLED")
 endif()
 
 if(${IS_REANIMATED_EXAMPLE_APP})
-    string(APPEND CMAKE_CXX_FLAGS " -DIS_REANIMATED_EXAMPLE_APP")
+    string(APPEND CMAKE_CXX_FLAGS " -DIS_REANIMATED_EXAMPLE_APP -Wpedantic")
 endif()
 
 if(NOT ${CMAKE_BUILD_TYPE} MATCHES "Debug")