Delete the useless MapreduceAction interface

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=122630519

java/google/registry/mapreduce/MapreduceAction.java

@@ -1,24 +0,0 @@
-// Copyright 2016 The Domain Registry Authors. All Rights Reserved.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//     http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package google.registry.mapreduce;
-
-import google.registry.request.Action;
-
-/**
- * Marker interface to denote an action intended for the Mapreduce queue.
- *
- * <p>Classes that implement this interface are expected to have {@link Action} set.
- */
-public interface MapreduceAction extends Runnable {}