remove created_by field from digital signage topic

Author: 514sid

topics/digital-signage/index.md

@@ -3,6 +3,5 @@ display_name: Digital signage
 short_description: Tools for managing and displaying multimedia content on digital screens.
 topic: digital-signage
 wikipedia_url: https://en.wikipedia.org/wiki/Digital_signage
-created_by: 514sid
 ---
 Digital signage is a segment of electronic signage that uses digital display technologies to present multimedia content in both public and private environments.