remove unused variable default
remove unused variable default

arbrandes/edx-configuration,EDUlib/configuration,edx/configuration,mitodl/configuration,edx/configuration,arbrandes/edx-configuration,EDUlib/configuration,arbrandes/edx-configuration,edx/configuration,mitodl/configuration,mitodl/configuration,arbrandes/edx-configuration,arbrandes/edx-configuration,edx/configuration,mitodl/configuration,EDUlib/configuration,EDUlib/configuration,EDUlib/configuration