Add unit test coverage that makes this check fail. Also add unit test
coverage for making sure trying to import something that isn't PEM fails
in the expected way.
Signed-off-by: Aaron Lehmann <aaron.lehmann@docker.com>
This function reads a zip file and populates the keystores with the keys
in the zip file. Root keys are left encrypted, and non-root keys are
decrypted before being added to the keystore.
The unit test first exports a repo's keys to a zip file, then imports it
into another repo. It checks that all the correct keys exist in the new
repo after the import operation.
Signed-off-by: Aaron Lehmann <aaron.lehmann@docker.com>