Remove unnecessary "throws" declarations

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

javatests/google/registry/export/ExportSnapshotActionTest.java

@@ -46,7 +46,7 @@ public class ExportSnapshotActionTest {
   private final ExportSnapshotAction action = new ExportSnapshotAction();
 
   @Before
-  public void before() throws Exception {
+  public void before() {
     action.clock = clock;
     action.backupService = backupService;
     action.response = response;