Perform some minor test cleanup

This standardizes use of annotations/inheritance/formatting across
tests, to make the code more legible and consistent.

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=161810734

javatests/google/registry/export/BigqueryPollJobActionTest.java

@@ -198,7 +198,6 @@ public class BigqueryPollJobActionTest {
   }
 
   @Test
-  @SuppressWarnings("unchecked")
   public void testJobStatusUnreadable() throws Exception {
     when(bigqueryJobsGet.execute()).thenThrow(IOException.class);
     thrown.expect(NotModifiedException.class);