Remove unnecessary "throws" declarations

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

java/google/registry/tools/CreateRegistrarGroupsCommand.java

@@ -49,7 +49,7 @@ public class CreateRegistrarGroupsCommand extends ConfirmingCommand
   }
 
   @Override
-  protected void init() throws IOException {
+  protected void init() {
     for (String clientId : clientIds) {
       Registrar registrar =
           checkArgumentPresent(