test!: use custom-repo-kernel-fix of stackhpc-image-elements

Signed-off-by: Jack Hodgkiss <jack@stackhpc.com>

Author: jackhodgkiss

etc/kayobe/stackhpc.yml

@@ -208,5 +208,5 @@ stackhpc_ca_secret_store: openbao
 stackhpc_dib_image_elements_repos:
   - repo: "https://github.com/stackhpc/stackhpc-image-elements"
     local: "{{ source_checkout_path }}/stackhpc-image-elements"
-    version: "v1.6.5"
+    version: "custom-repo-kernel-fix"
     elements_path: "elements"