When running acceptance tests via Litmus, the Puppet::Util::Windows::APITypes::FFI module from lib/puppet/util/windows/api_types.rb is loaded via the puppet gem.
Unfortunately this module always gets loaded twice and a warning is returned to the commandline:
C:/src/puppetlabs-java_ks/.bundle/gems/ruby/2.5.0/gems/puppet-6.4.2-x64-mingw32/lib/puppet/util/windows/api_types.rb:6: warning: already initialized constant FFI::WIN32_FALSE C:/src/puppetlabs-java_ks/.bundle/gems/ruby/2.5.0/gems/pdk-1.10.0/lib/pdk/util/windows/api_types.rb:6: warning: previous definition of WIN32_FALSE was here C:/src/puppetlabs-java_ks/.bundle/gems/ruby/2.5.0/gems/puppet-6.4.2-x64-mingw32/lib/puppet/util/windows/api_types.rb:9: warning: already initialized constant FFI::ERROR_SUCCESS C:/src/puppetlabs-java_ks/.bundle/gems/ruby/2.5.0/gems/pdk-1.10.0/lib/pdk/util/windows/api_types.rb:9: warning: previous definition of ERROR_SUCCESS was here