Silence Xcode warning (#23880)

Summary:
Fixes a warning in React Xcode proj. Should be a trivial change.

[iOS] [Fixed] - uncaptured lambda warning
Pull Request resolved: https://github.com/facebook/react-native/pull/23880

Differential Revision: D14435848

Pulled By: cpojer

fbshipit-source-id: 83c126c7401ac32b769ff17172f4f4ae576bd771

React/CxxModule/RCTNativeModule.mm

@@ -67,6 +67,8 @@ void RCTNativeModule::invoke(unsigned int methodId, folly::dynamic &&params, int
     if (callId != -1) {
       fbsystrace_end_async_flow(TRACE_TAG_REACT_APPS, "native", callId);
     }
+    #else
+    (void)(callId);
     #endif
     invokeInner(weakBridge, weakModuleData, methodId, std::move(params));
   };