Fix error message in ami-publisher list-unpackers subcommand.
Fix error message in ami-publisher list-unpackers subcommand.

Symantec/Dominator,keep94/Dominator,rgooch/Dominator,rgooch/Dominator,keep94/Dominator,rgooch/Dominator,Symantec/Dominator,keep94/Dominator,Symantec/Dominator