fix(ios, expo): use modern import style, required by Expo 44+

Expo 44+ enforces use of new import style for React headers, and they
are supported far enough back in time on react-native versions this should
not be breaking for anyone

packages/app/scripts/genversion-ios.js

@@ -20,7 +20,7 @@ const template = `/**
  *
  */
 
-#import "RCTVersion.h"
+#import <React/RCTVersion.h>
 
 // generated file - do not modify or commit
 NSString* const RNFBVersionString = @"VERSION";