init manifest for complex promo test

bubble-server/src/test/java/bubble/test/promo/FirstMonthAndReferralMonthPromotionTest.java

@@ -7,6 +7,8 @@ import org.junit.Test;
 @Slf4j
 public class FirstMonthAndReferralMonthPromotionTest extends PaymentTestBase {
 
+    @Override protected String getManifest() { return "promo/1mo_and_referral/manifest_1m_and_referral"; }
+
     @Test public void testFirstMonthAndMultipleReferralMonthsFree () throws Exception {
         modelTest("promo/first_month_and_multiple_referral_months_free");
     }

bubble-server/src/test/resources/models/promo/1mo_and_referral/manifest_1mo_and_referral.json

@@ -0,0 +1,7 @@
+[
+  "manifest-test",
+  "promo/1mo/cloudService_1mo",
+  "promo/1mo/promotion_1mo",
+  "promo/referral/cloudService_referral",
+  "promo/referral/promotion_referral"
+]