Bump FlipperKit version on iOS to be compatible with react-native-fli…

…pper

This diff updated FlipperKit to be compatible with the latest react-native-flipper version. Tested by upgrading the ReactNativeFlipperExample (https://github.com/facebook/flipper/tree/master/react-native/ReactNativeFlipperExample) to RN 0.62.0-rc.3 and verified the example plugin works. (In D20221558)

scripts/react_native_pods.rb

@@ -57,7 +57,7 @@ def use_react_native! (options={})
   end
 end
 
-def use_flipper!(version = '~> 0.30.2')
+def use_flipper!(version = '~> 0.32.2')
   pod 'FlipperKit', version, :configuration => 'Debug'
   pod 'FlipperKit/FlipperKitLayoutPlugin', version, :configuration => 'Debug'
   pod 'FlipperKit/SKIOSNetworkPlugin', version, :configuration => 'Debug'