Missed these before, noticed while making a new one.
Also a copy paste error left one shasum incorrect.
Signed-off-by: Justin Cormack <justin.cormack@docker.com>
When building the base images always test signatures.
This will be the default at some point.
Add a test that content trust is working.
Signed-off-by: Justin Cormack <justin.cormack@docker.com>