Update to react-native 0.64 and enable Hermes

Summary:
allow-large-files

Per title. hermes enabled so that we can verify the hermes debugger works.

Reviewed By: passy

Differential Revision: D27229331

fbshipit-source-id: c2e45151b9d2097edc7e79f54eb89f9d110899d6

react-native/ReactNativeFlipperExample/ios/Podfile

@@ -5,7 +5,10 @@ platform :ios, '10.0'
 
 target 'ReactNativeFlipperExample' do
   config = use_native_modules!
-  use_react_native!(:path => config["reactNativePath"])
+  use_react_native!(
+    :path => config["reactNativePath"],
+    :hermes_enabled => true
+  )
 
   target 'ReactNativeFlipperExampleTests' do
     inherit! :complete
@@ -21,12 +24,3 @@ target 'ReactNativeFlipperExample' do
     flipper_post_install(installer)
   end
 end
-
-target 'ReactNativeFlipperExample-tvOS' do
-  # Pods for ReactNativeFlipperExample-tvOS
-
-  target 'ReactNativeFlipperExample-tvOSTests' do
-    inherit! :search_paths
-    # Pods for testing
-  end
-end