chore(deploy): checkout Gemfile.lock before deploying

Author: PLNech

fastlane/Fastfile

@@ -31,6 +31,7 @@ platform :android do
     puts "New version: #{version_number}"
 
     # Ensure branch is master & WC clean, then pull changes
+    git checkout Gemfile.lock # Ignore different bundle version changing Gemfile https://discuss.bitrise.io/t/5176/5
     prepare_git()
 
     # Generate changelog updates