[!!!][TASK] Remove "Database Relations" backend module (#704)

References: TYPO3-Documentation/Changelog-To-Doc#1239
Releases: main

Author: linawolf

Documentation/Concepts/Backend/SystemModules/Index.rst

@@ -116,10 +116,6 @@ Record Statistics
     Shows a count of the various records in the database,
     broken down by type for pages and content elements.
 
-Relations
-    Checks if certain relations are empty or broken, typically
-    used to check if files are being referenced.
-
 Search
     A tool to search through the whole database. It offers an
     advanced mode which is similar to a visual query builder.