Fix family subscription tests (thanks zach!)

test/controllers/subscriptions_controller_test.rb

@@ -32,8 +32,6 @@ class SubscriptionsControllerTest < ActionDispatch::IntegrationTest
   end
 
   test "users who have already trialed cannot create a new subscription" do
-    @family.start_trial_subscription!
-
     assert_no_difference "Subscription.count" do
       post subscription_path
     end

test/models/subscription_test.rb

@@ -2,7 +2,7 @@ require "test_helper"
 
 class SubscriptionTest < ActiveSupport::TestCase
   setup do
-    @family = families(:empty)
+    @family = Family.create!(name: "Test Family")
   end
 
   test "can create subscription without stripe details if trial" do