This commit changes the spec file so that most of the repositories
are taken from the `images` library. See images PR#1112 for details.
Note that we still need the -no-auth-keys and the centos-stream
symlinks.
Update the RPM GPG keys in the c10s repos that are shipped in the RPM,
to the one that is used in our testing c10s repos. This will fix image
builds on c10s.
Signed-off-by: Tomáš Hozza <thozza@redhat.com>