Add RockyLinux support

templates/rockylinux.repo.j2

@@ -1,10 +0,0 @@
-[rocky-baseos]
-name=Rocky Linux $releasever - BaseOS
-mirrorlist=https://mirrors.rockylinux.org/mirrorlist?arch=$basearch&repo=BaseOS-$releasever
-#baseurl=http://dl.rockylinux.org/$contentdir/$releasever/BaseOS/$basearch/os/
-gpgcheck=1
-enabled=1
-countme=1
-gpgkey=https://dl.rockylinux.org/pub/rocky/RPM-GPG-KEY-Rocky-$releasever
-metadata_expire=86400
-enabled_metadata=1