Remove unnecessary "throws" declarations

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

javatests/google/registry/model/EntityTestCase.java

@@ -60,7 +60,7 @@ public class EntityTestCase {
   protected FakeClock clock = new FakeClock(DateTime.now(UTC));
 
   @Before
-  public void injectClock() throws Exception {
+  public void injectClock() {
     inject.setStaticField(Ofy.class, "clock", clock);
   }