Move "Open Lines" to product_price_list module

The product_price_list_dates module adds a button to open the price list lines in a new tab such that filtering/import is possible. It was only in this module because the context_domain was specific to this module but since 30fb7fbf4767 it is possible to customize the action of a button such that the context_domain could be added by module extension. So the button could be define in the product_price_list module and be available for every use case.