Fix Seedbank::DSL#original_seeds_file

Author: nard-tech

lib/seedbank/dsl.rb

@@ -41,7 +41,7 @@ def define_seed_task(seed_file, *args)
       end
 
       def original_seeds_file
-        @_original_seeds_file ||= existent(original_seeds_file_expanded('../seeds.rb', seeds_root))
+        @_original_seeds_file ||= existent(original_seeds_file_expanded(Seedbank.original_seeds_file, seeds_root))
       end
 
       def seeds_root