Fix image tags CI check

Author: Alex-Welsh

etc/kayobe/environments/ci-aio/stackhpc-ci.yml

@@ -55,7 +55,7 @@ stackhpc_include_os_minor_version_in_repo_url: true
 
 # Override Pulp credentials to allow querying container image tags in the
 # check-tags.yml custom playbook.
-pulp_url: "{{ stackhpc_repo_mirror_url }}"
+pulp_url: "{{ stackhpc_release_pulp_url }}"
 pulp_username: "skc-ci-aio-epoxy"
 pulp_password: !vault |
   $ANSIBLE_VAULT;1.1;AES256