[chore] Fix identifying attribute rendering #2458 (#2459)

Author: thompson-tomo

templates/registry/markdown/entity_namespace.md.j2

@@ -20,7 +20,7 @@
 
 **Description:** {{ e.brief | trim }}
 
-{%- if desc_attrs | length > 0 %}
+{%- if id_attrs | length > 0 %}
 
 **Identifying Attributes:**