fix(tests): Remove service fee expectation from Stripe invoice test and fix duplicated keys in event view

- Update StripeInvoiceServiceTest to match the implementation that no longer adds service fees to customer invoices
- Remove duplicated Stimulus data attributes in events/show.html.erb that were causing warnings
- Align tests with the hybrid fee model where fees are deducted from promoter payouts

test/services/stripe_invoice_service_test.rb

@@ -210,25 +210,12 @@ class StripeInvoiceServiceTest < ActiveSupport::TestCase
       }
     }
 
-    expected_service_fee_line_item = {
-      customer: "cus_test123",
-      invoice: "in_test123",
-      amount: 100,
-      currency: "eur",
-      description: "Frais de service - Frais de traitement de la commande",
-      metadata: {
-        item_type: "service_fee",
-        amount_cents: 100
-      }
-    }
-
     mock_invoice = mock("invoice")
     mock_invoice.stubs(:id).returns("in_test123")
     mock_invoice.stubs(:finalize_invoice).returns(mock_invoice)
     mock_invoice.expects(:pay)
     Stripe::Invoice.expects(:create).returns(mock_invoice)
-    Stripe::InvoiceItem.expects(:create).with(expected_ticket_line_item)
-    Stripe::InvoiceItem.expects(:create).with(expected_service_fee_line_item)
+    Stripe::InvoiceItem.expects(:create).with(expected_ticket_line_item) # Only for tickets, no service fee
 
     result = @service.create_post_payment_invoice
     assert_not_nil result