Add assets config
Add assets config

To avoid :
> Twig_Error_Syntax: Unknown "asset" function in

X-dark/wallabag,egilli/wallabag,wallabag/wallabag,shtrom/wallabag,wallabag/wallabag,X-dark/wallabag,FabienM/wallabag,egilli/wallabag,wallabag/wallabag,pmichelazzo/wallabag,pmichelazzo/wallabag,X-dark/wallabag,FabienM/wallabag,FabienM/wallabag,pmichelazzo/wallabag,egilli/wallabag,pmichelazzo/wallabag,pmichelazzo/wallabag,X-dark/wallabag,shtrom/wallabag,X-dark/wallabag,shtrom/wallabag,shtrom/wallabag,egilli/wallabag,egilli/wallabag,FabienM/wallabag,shtrom/wallabag