fix parsing of videos with missing description
fix parsing of videos with missing description

Boussadia/weboob,sputnick-dev/weboob,sputnick-dev/weboob,eirmag/weboob,willprice/weboob,sputnick-dev/weboob,Boussadia/weboob,eirmag/weboob,yannrouillard/weboob,RouxRC/weboob,franek/weboob,frankrousseau/weboob,RouxRC/weboob,RouxRC/weboob,laurent-george/weboob,nojhan/weboob-devel,franek/weboob,Konubinix/weboob,frankrousseau/weboob,Konubinix/weboob,nojhan/weboob-devel,willprice/weboob,Konubinix/weboob,frankrousseau/weboob,Boussadia/weboob,willprice/weboob,franek/weboob,yannrouillard/weboob,eirmag/weboob,Boussadia/weboob,yannrouillard/weboob,laurent-george/weboob,laurent-george/weboob,nojhan/weboob-devel