Fix duplicate error registration

Author: rmosolgo

lib/graphql/execution/batching/field_compatibility.rb

@@ -112,15 +112,15 @@ def resolve_batch(frs, objects, context, kwargs)
               end
             rescue GraphQL::Error => err
               if err.respond_to?(:path=) # TODO sort out error hierarchy so I can match these without a respond_to check
-                frs.add_graphql_error(err)
+                err
               else
                 raise
               end
             rescue StandardError => stderr
               begin
                 context.query.handle_or_reraise(stderr)
               rescue GraphQL::ExecutionError => ex_err
-                frs.add_graphql_error(ex_err)
+                ex_err
               end
             end
           elsif objects.first.is_a?(Hash)

lib/graphql/execution/batching/field_resolve_step.rb

@@ -138,7 +138,7 @@ def sync(lazy)
         rescue GraphQL::UnauthorizedError => auth_err
           @runner.schema.unauthorized_object(auth_err)
         rescue GraphQL::ExecutionError => err
-          add_graphql_error(err)
+          err
         end
 
         def call