finalize covering of AlterEventDataEventTest

[WengerK]

There is @todo on this code for following cases:

      // @todo add product impression example.
      'Product impressions' => [
        [
          'event' => EventTrackerService::EVENT_PRODUCT_IMPRESSIONS,
          'ecommerce' => [],
        ],
      ],

      // @todo add product click example.
      'Product click' => [
        [
          'event' => EventTrackerService::EVENT_PRODUCT_CLICK,
          'ecommerce' => [],
        ],
      ],

      // @todo add checkout option example.
      'Checkout option' => [
        [
          'event' => EventTrackerService::EVENT_CHECKOUT_OPTION,
          'ecommerce' => [],
        ],
      ],