Steps to reproduce:

1. Install fresh v4.1 Ibexa Commerce.
2. Create Product Content Type anywhere.
3. Fill the required data and publish.

Result:
You will be presented with an exception:

Argument 1 passed to Ibexa\ProductCatalog\Dispatcher\ProductServiceDispatcher::getProduct() must be of the type string, int given, called in /Users/bartek/Projects/41/vendor/ibexa/product-catalog/src/lib/Bridge/CatalogDataProvider.php on line 95

Expected result:
You should be able to view content after publication.

Note:
The issue doesn't occur on v4.0.3.