Fix link name reference if content type is invalid

Currently, the name of a custom link is referenced
as if it is an object attribute which causes a break
due to it actually being a dictionary.

This minor change means that the startup script won't
*ahem* fail upon failing :)

Signed-Off-by: Marcus Crane <marcus.crane@daimler.com>

startup_scripts/280_custom_links.py

@@ -23,7 +23,7 @@ for link in custom_links:
     if link["content_type_id"] is None:
         print(
             "⚠️ Unable to create Custom Link '{0}': The content_type '{1}' is unknown".format(
-                link.name, content_type
+                link.get('name'), content_type
             )
         )
         continue