Fix xref guidelines for contrib doc, make 1 scenario

openshiftGH-53958: Fix xref guidelines for contrib doc

As called out in the comments: openshift#53958

This updates the `/baz/zig` and `/baz/zag` examples.

@openshift/team-documentation PTAL

Author: bobfuru

contributing_to_docs/doc_guidelines.adoc

@@ -747,19 +747,14 @@ IMPORTANT: You cannot link to a repository that is hosted on www.github.com.
 TIP: If you want to build a link from a URL _without_ changing the text from the actual URL, just print the URL without adding a `[friendly text]` block at the end; it will automatically be rendered as a link.
 
 === Links to internal content
-There are two scenarios for linking to other assemblies:
-
-1. Link to another file that exists in the same directory.
-2. Link to another file that exists in a separate directory.
-
-The following examples use the example directory structure shown here:
+If you want to link to other assemblies, refer to the following example directory structure shown here:
 ....
 /
 /foo
 /foo/bar.adoc
 /baz
-/baz/zig.adoc
-/baz/zag.adoc
+xref:../baz/zig.adoc
+xref:../baz/zag.adoc
 ....
 
 *Link to assembly in same directory*