fix: [server caching] only push data to redis / logs if there's something to push
fix: [server caching] only push data to redis / logs if there's something to push

- avoids the count() notice if no data was returned by the remote

SteveClement/MISP,SteveClement/MISP,MISP/MISP,MISP/MISP,MISP/MISP,MISP/MISP,SteveClement/MISP,SteveClement/MISP,SteveClement/MISP,MISP/MISP