Use geo-distributed mirror for Alma URL

Rackspace's mirror network is geographically distributed.  Requesting
the mirror.rackspace.com endpoint will point you at the closest mirror
to your location.  It will even route you to the next nearest mirror in
the case of an outage.  Hard coding this to the lon.mirror.rackspace.com
endpoint forces every user to route through London, regardless of their
location.

quickget

@@ -980,7 +980,7 @@ function get_alma() {
     local EDITION="${1:-}"
     local HASH=""
     local ISO="AlmaLinux-${RELEASE}-x86_64-${EDITION}.iso"
-    local URL="http://lon.mirror.rackspace.com/almalinux/${RELEASE/beta-1/beta}/isos/x86_64/"
+    local URL="https://mirror.rackspace.com/almalinux/${RELEASE/beta-1/beta}/isos/x86_64/"
     HASH="$(wget -q -O- "${URL}/CHECKSUM" | grep "(${ISO}" | cut -d' ' -f4)"
     echo "${URL}/${ISO} ${HASH}"
 }