[api] drop old 20140604101042 migration, which is obsolete now

src/api/db/attribute_descriptions.rb

@@ -26,6 +26,7 @@ def update_all_attrib_type_descriptions
 
   for k in d.keys do
     at = ans.attrib_types.where(name: k).first
+    next unless at # might be called in older migrations
     at.description = d[k]
     at.save
   end

src/api/db/structure.sql

@@ -1557,8 +1557,6 @@ INSERT INTO schema_migrations (version) VALUES ('20140219185200');
 
 INSERT INTO schema_migrations (version) VALUES ('20140516182719');
 
-INSERT INTO schema_migrations (version) VALUES ('20140604101042');
-
 INSERT INTO schema_migrations (version) VALUES ('20140624101042');
 
 INSERT INTO schema_migrations (version) VALUES ('20140627071042');