appmanager: handle empty response from storage
appmanager: handle empty response from storage

MalmoUniversity-DA366A/calvin-base,EricssonResearch/calvin-base,KaptenJon/calvin-base,les69/calvin-base,les69/calvin-base,les69/calvin-base,EricssonResearch/calvin-base,EricssonResearch/calvin-base,les69/calvin-base,KaptenJon/calvin-base,MalmoUniversity-DA366A/calvin-base,MalmoUniversity-DA366A/calvin-base,EricssonResearch/calvin-base,KaptenJon/calvin-base