Add a button in the admin panel to check OT&E status of a registrar

For now, it only displays a status of "Passed: true|false" or an error message in simple text. In further work we will make the UI nicer.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=229971564

javatests/google/registry/model/OteStatsTest.java

@@ -31,7 +31,7 @@ public final class OteStatsTest {
 
   @Before
   public void init() throws Exception {
-    OteStatsTestHelper.setupHistoryEntries();
+    OteStatsTestHelper.setupHistoryEntries("blobio");
   }
 
   @Test