Remove unnecessary (and incorrect) conditional

Introduced in ef7fa51

Author: wagenet

lib/graphiti/util/serializer_relationships.rb

@@ -58,9 +58,7 @@ def block
               self_ref.send(:validate_link!) unless self_ref.send(:eagerly_validate_links?)
 
               link(:related) do
-                if self_ref
-                  ::Graphiti::Util::Link.new(sideload_ref, @object).generate
-                end
+                ::Graphiti::Util::Link.new(sideload_ref, @object).generate
               end
             end
           end