Fix RuboCop offense Style/ReturnNilInPredicateMethodDefinition (#39111).

git-svn-id: https://svn.redmine.org/redmine/trunk@22643 e93f8b46-1217-0410-a6f0-8f06a7374b81

lib/redmine/asset_path.rb

@@ -80,13 +80,13 @@ module Redmine
       end
 
       def parent_path?(path, other)
-        return nil if other == path
+        return false if other == path
 
         path.ascend.any?(other)
       end
 
       def child_path?(path, other)
-        return nil if path == other
+        return false if path == other
 
         other.ascend.any?(path)
       end