fix: Add missing space in method documentation (facebook#35303)

Summary:
probably the smallest PR I ever submitted, but it was bothering me lol

There was a missing space in the method doc.

## Changelog

Add space to the method doc
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[iOS] [Fixed] - Add missing space in method documentation comment

Pull Request resolved: facebook#35303

Reviewed By: jacdebug

Differential Revision: D41182765

Pulled By: cipolleschi

fbshipit-source-id: ebe5d56072137547e543a312c66cc3234142db13

template/ios/HelloWorld/AppDelegate.mm

@@ -19,7 +19,7 @@ - (NSURL *)sourceURLForBridge:(RCTBridge *)bridge
 #endif
 }
 
-/// This method controls whether the `concurrentRoot`feature of React18 is turned on or off.
+/// This method controls whether the `concurrentRoot` feature of React18 is turned on or off.
 ///
 /// @see: https://reactjs.org/blog/2022/03/29/react-v18.html
 /// @note: This requires to be rendering on Fabric (i.e. on the New Architecture).