Add libffi-dev to discovery
Add libffi-dev to discovery

hks-epod/configuration,michaelsteiner19/open-edx-configuration,pobrejuanito/configuration,rue89-tech/configuration,marcore/configuration,Stanford-Online/configuration,hastexo/edx-configuration,rue89-tech/configuration,Livit/Livit.Learn.EdX.configuration,michaelsteiner19/open-edx-configuration,proversity-org/configuration,jorgeomarmh/configuration,armaan/edx-configuration,nunpa/configuration,open-craft/configuration,michaelsteiner19/open-edx-configuration,appsembler/configuration,gsehub/configuration,marcore/configuration,open-craft/configuration,stvstnfrd/configuration,appsembler/configuration,Stanford-Online/configuration,edx/configuration,proversity-org/configuration,mitodl/configuration,Livit/Livit.Learn.EdX.configuration,EDUlib/configuration,gsehub/configuration,edx/configuration,hastexo/edx-configuration,jorgeomarmh/configuration,appsembler/configuration,arbrandes/edx-configuration,pobrejuanito/configuration,open-craft/configuration,jorgeomarmh/configuration,rue89-tech/configuration,nunpa/configuration,Livit/Livit.Learn.EdX.configuration,edx/configuration,hastexo/edx-configuration,hks-epod/configuration,arbrandes/edx-configuration,openfun/configuration,hks-epod/configuration,pobrejuanito/configuration,stvstnfrd/configuration,mitodl/configuration,nunpa/configuration,mitodl/configuration,appsembler/configuration,stvstnfrd/configuration,stvstnfrd/configuration,armaan/edx-configuration,marcore/configuration,armaan/edx-configuration,michaelsteiner19/open-edx-configuration,gsehub/configuration,EDUlib/configuration,Livit/Livit.Learn.EdX.configuration,Stanford-Online/configuration,openfun/configuration,openfun/configuration,edx/configuration,EDUlib/configuration,stvstnfrd/configuration,Stanford-Online/configuration,gsehub/configuration,marcore/configuration,proversity-org/configuration,hks-epod/configuration,armaan/edx-configuration,rue89-tech/configuration,hks-epod/configuration,open-craft/configuration,pobrejuanito/configuration,rue89-tech/configuration,mitodl/configuration,EDUlib/configuration,arbrandes/edx-configuration,EDUlib/configuration,proversity-org/configuration,openfun/configuration,hastexo/edx-configuration,gsehub/configuration,jorgeomarmh/configuration,hastexo/edx-configuration,arbrandes/edx-configuration,nunpa/configuration,Stanford-Online/configuration,arbrandes/edx-configuration,proversity-org/configuration