Fix failing build by not propagating deployment target to deps (#2103)

Summary:
Pull Request resolved: https://github.com/facebook/flipper/pull/2103

Local builds break if the deploy target of deps isn't new enough. It seems that the project podfile is not respected in this regard, as reported here: https://stackoverflow.com/a/37289688/1983583. Will see if there is a better way to fix this.

Reviewed By: jknoxville

Differential Revision: D27328025

fbshipit-source-id: 6c5ac2dc88c3dd90dd84ce691a4f8e42188f96c2

react-native/ReactNativeFlipperExample/ios/Podfile

@@ -22,5 +22,11 @@ target 'ReactNativeFlipperExample' do
   use_flipper!({ 'Flipper' => '0.82.0' })
   post_install do |installer|
     flipper_post_install(installer)
+    # based on https://stackoverflow.com/a/37289688/1983583
+    installer.pods_project.targets.each do |target|
+      target.build_configurations.each do |config|
+        config.build_settings['IPHONEOS_DEPLOYMENT_TARGET'] = '10.0'
+      end
+    end
   end
 end