iOS downgrade error to warning when invoking native module with invalid bridge

Summary: A bunch of flows including JS reload and e2e tests seem to hit the race condition, causing redbox. For now, make it a warning to unblock.

Differential Revision: D9327418

fbshipit-source-id: a72b378d88f7566268fd9415fbd34225c8b931e7

React/CxxModule/RCTNativeModule.mm

@@ -79,8 +79,8 @@ void RCTNativeModule::invoke(unsigned int methodId, folly::dynamic &&params, int
       dispatch_async(queue, block);
     }
   } else {
-    RCTLogError(@"Attempted to invoke `%u` (method ID) on `%@` (NativeModule name) with an invalid bridge.",
-                methodId, m_moduleData.name);
+    RCTLogWarn(@"Attempted to invoke `%u` (method ID) on `%@` (NativeModule name) with an invalid bridge.",
+               methodId, m_moduleData.name);
   }
 }