Switch to quay.io for rockylinux base image

Author: elelaysh

elements/rocky-container-stackhpc/containerfiles/9-stackhpc

@@ -1,7 +1,7 @@
 # Based on https://github.com/openstack/diskimage-builder/blob/master/diskimage_builder/elements/rocky-container/containerfiles/9
 # For least surprise when a new minor version is out, specify the full version, eg `ROCKY_VERSION=9.7`
 ARG ROCKY_VERSION=9
-FROM docker.io/rockylinux/rockylinux:${ROCKY_VERSION}
+FROM quay.io/rockylinux/rockylinux:${ROCKY_VERSION}
 ARG ROCKY_USE_CUSTOM_DNF_MIRRORS="false"
 # Comma-delimited list of repo URLs
 ARG ROCKY_CUSTOM_DNF_MIRROR_URLS