[BootstrapAdminUi] breadcrumbs template crashes when no title is configured

[camilleislasse]

Bug description

The template @SyliusBootstrapAdminUi/shared/crud/index/content/header/breadcrumbs.html.twig crashes when configuration.title is not set on the breadcrumbs hookable. The else branch accesses hookable_metadata.configuration.title without a |default() filter, causing a ScalarDataBag property access exception.

Same on Sylius : Sylius/Sylius#18933