No registries warning

When no /etc/containers/registries.conf is found, log a warning message.

Signed-off-by: baude <bbaude@redhat.com>

Closes: #338
Approved by: mheon
This commit is contained in:
Internal Server Error - Gitea: Git with a cup of tea
500 Internal Server Error

Gitea Version: 1.28.0+dev-477-g8b6ad49a5f