metal3 tips: fix hard-coded versions

(cherry picked from commit a81b56a)

Author: hardys

asciidoc/tips/metal3.adoc

@@ -118,7 +118,7 @@ How to get the UUIDs you need:
 now in the output files you should have the UUIDs that you can use in your configuration.
 
 3. Alternatively, if you don't use OpenSUSE or SLES, you can use the nmc through the Edge Image Builder container image:
-`podman run -it --rm -v $(pwd):/path/to/your/config:Z --entrypoint=/usr/bin/nmc registry.suse.com/edge/3.3/edge-image-builder:1.2.1 generate --confi
+`podman run -it --rm -v $(pwd):/path/to/your/config:Z --entrypoint=/usr/bin/nmc registry.suse.com/edge/{version-edge-registry}/edge-image-builder:{version-eib} generate --confi
 g-dir /path/to/your/config --output-dir /where/you/want/it`
 
 == `BareMetalHost` selection and Cluster association