image-by-digest.bats: print output
image-by-digest.bats: print output

Display the output from commands before we check their exit status, so
that we can see what they output if a check fails.

Signed-off-by: Nalin Dahyabhai <f562fcb2a0b898bf0be1afc867ea92325d8f825f@redhat.com>

rhatdan/storage,rhatdan/storage,containers/storage,containers/storage,rhatdan/storage,containers/storage