Avoid RCTUnsafeExecuteOnMainQueueSync from RCTUIManager

These calls are only needed for a temporary Fabric workaround and would result in a deadlock since we also call `RCTUnsafeExecuteOnUIManagerQueueSync` from the main thread during window resize.

This is needed for now in Fabric only to call the temporary `componentViewName_DO_NOT_USE_THIS_IS_BROKEN` workaround on views, which we don't have on desktop since we're a way off from using Fabric (and hopefully this workaround will be gone then).

It was originally added here facebook@ffc7ec9

At Meta we have disabled these lines since May 2021 to fix crashes in production.

React/Modules/RCTUIManager.m

@@ -354,6 +354,7 @@ - (NSString *)viewNameForReactTag:(NSNumber *)reactTag
     return name;
   }
 
+#if !TARGET_OS_OSX // [TODO(macOS GH#774)
   __block RCTPlatformView *view; // TODO(macOS GH#774)
   RCTUnsafeExecuteOnMainQueueSync(^{
     view = self->_viewRegistry[reactTag];
@@ -367,6 +368,7 @@ - (NSString *)viewNameForReactTag:(NSNumber *)reactTag
   }
 
 #pragma clang diagnostic pop
+#endif // ]TODO(macOS GH#774)
   return nil;
 }
 
@@ -1135,6 +1137,7 @@ - (void)synchronouslyUpdateViewOnUIThread:(NSNumber *)reactTag viewName:(NSStrin
   RCTShadowView *shadowView = _shadowViewRegistry[reactTag];
   RCTComponentData *componentData = _componentDataByName[shadowView.viewName];
 
+#if !TARGET_OS_OSX // [TODO(macOS GH#774)
   // Achtung! Achtung!
   // This is a remarkably hacky and ugly workaround.
   // We need this only temporary for some testing. We need this hack until Fabric fully implements command-execution
@@ -1152,6 +1155,7 @@ - (void)synchronouslyUpdateViewOnUIThread:(NSNumber *)reactTag viewName:(NSStrin
     }
   }
 #pragma clang diagnostic pop
+#endif // ]TODO(macOS GH#774)
 
   Class managerClass = componentData.managerClass;
   RCTModuleData *moduleData = [_bridge moduleDataForName:RCTBridgeModuleNameForClass(managerClass)];