Update various tests to work with SQL as well (#1078)

* Update various tests to work with SQL as well

The main weird bit here is adding a method in DatabaseHelper to
retrieve and initialize all objects in either database. The
initialization is necessary since it's used post-command-dry-run to make
sure that no changes were actually made.

core/src/main/java/google/registry/persistence/transaction/JpaTransactionManagerImpl.java

@@ -37,6 +37,7 @@ import google.registry.model.index.ForeignKeyIndex.ForeignKeyDomainIndex;
 import google.registry.model.index.ForeignKeyIndex.ForeignKeyHostIndex;
 import google.registry.model.ofy.DatastoreTransactionManager;
 import google.registry.model.server.KmsSecret;
+import google.registry.model.tmch.ClaimsListShard.ClaimsListSingleton;
 import google.registry.persistence.JpaRetries;
 import google.registry.persistence.VKey;
 import google.registry.util.Clock;
@@ -73,6 +74,7 @@ public class JpaTransactionManagerImpl implements JpaTransactionManager {
   // TODO(b/176108270): Remove this property after database migration.
   private static final ImmutableSet<Class<? extends ImmutableObject>> IGNORED_ENTITY_CLASSES =
       ImmutableSet.of(
+          ClaimsListSingleton.class,
           EppResourceIndex.class,
           ForeignKeyContactIndex.class,
           ForeignKeyDomainIndex.class,