Pass the withoutCannedData boolean to JpaTransactionManagerExtension builder (#1678)

This is an oversight from #1673

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core/src/test/java/google/registry/persistence/transaction/JpaTransactionManagerExtension.java

@@ -118,7 +118,7 @@ abstract class JpaTransactionManagerExtension implements BeforeEachCallback, Aft
   private boolean includeNomulusSchema = true;
 
   // Whether to prepolulate some registrars for ease of testing.
-  private boolean withCannedData = false;
+  private final boolean withCannedData;
 
   JpaTransactionManagerExtension(
       Clock clock,

core/src/test/java/google/registry/testing/AppEngineExtension.java

@@ -375,6 +375,9 @@ public final class AppEngineExtension implements BeforeEachCallback, AfterEachCa
     if (withCloudSql) {
       JpaTestExtensions.Builder builder =
           new JpaTestExtensions.Builder().withEntityClass(jpaTestEntities.toArray(new Class[0]));
+      if (withoutCannedData) {
+        builder.withoutCannedData();
+      }
       if (clock != null) {
         builder.withClock(clock);
       }