fix ruby syntax error

Author: hawkrives

fastlane/lib/util.rb

@@ -18,6 +18,7 @@ def hockeyapp_version_commit
 def current_build_number
   if ENV.key?('TRAVIS_BUILD_NUMBER')
     return ENV['TRAVIS_BUILD_NUMBER']
+  end
 
   begin
     (latest_testflight_build_number + 1).to_s