centos stream 9 x64 min

Provide Centos Stream 9 min environment for x64 architecture.

from_scratch/centos-stream-8.yaml

@@ -10,9 +10,6 @@ extend: centos-stream-base.yaml
 
 global:
   release_number: 8
-  installer_iso_finder_mirror_url: http://mirror.in2p3.fr/linux/CentOS/
-  mirror_base_url: http://mirror.centos.org/centos/
-  mirror_url: $${mirror_base_url}$${release}-stream/BaseOS/$${arch}/os
 
 bootstrap:
   - "@base"