Only long, unformatted, text fields do not show up in User Field Mappings -> Fields

Problem/Motivation

If you add a "Text (plain, long)" field to your user entity type, it does not show up as an option under "User Field Mappings" in the "Fields" section of the Attributes -> Settings page.

Thus, I have no way to store the data I need to store in it.

Steps to reproduce

Add a "Text (plain, long)" field to your User entity type and visit the setting page.

Proposed resolution

Add the "Text (plain, long)" type to the types allowed in the CasAttributesSettings buildForm method.

Assuming that there isn't a reason for specifically excluding the "Text (plain, long)" type...

Thanks in advance!