Remove unnecessary "throws" declarations

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=201058582

java/google/registry/mapreduce/inputs/ChildEntityReader.java

@@ -193,7 +193,7 @@ class ChildEntityReader<R extends EppResource, I extends ImmutableObject> extend
   }
 
   @Override
-  public void beginShard() throws IOException {
+  public void beginShard() {
     eppResourceEntityReader.beginShard();
   }