FIX merchant regression (#659)

test/models/family_test.rb

@@ -6,4 +6,12 @@ class FamilyTest < ActiveSupport::TestCase
   def setup
     @syncable = families(:dylan_family)
   end
+
+  test "available_merchants includes family merchants without transactions" do
+    family = families(:dylan_family)
+
+    new_merchant = family.merchants.create!(name: "New Test Merchant")
+
+    assert_includes family.available_merchants, new_merchant
+  end
 end