EntityType::getLowercaseLabel() is now deprecated. Please use EntityType::getSingularLabel() instead.
Background
This step is necessary to allow correctly translate the user interface into German.
Module developers that define custom entity types are encouraged to use the label_singular entity annotation key to specify a mid-sentence label for the entity type. In English, this usually begins with a lower-case character. If no label_singular is given, the general entity type label annotation is converted to lower case.
Translators to German can then use start the translated label with a capital letter. This was not possible without deprecating EntityType::getLowercaseLabel(), which predates label_singular introduced in Entity types can specify plural labels now.
For more information, see the API documentation of EntityType::getSingularLabel().
