Cannot create externally mapped role for SAML

Due to "Mapped Role" being a select field, it is not possible to create an "Externally Mapped" Role for SAML.

To reproduce, via the UI --> "Create Role" --> "External Role Mapping" --> "SAML", observe that the "Mapped Role" field is an empty select.

Expected:

For SAML role mapping, "Mapped Role" should be a text field.

Workaround:

Create a "Nexus Role" with the same name as the SAML group you wish to map or use the Nexus REST API to map the role.

PR

https://github.com/sonatype/nexus-internal/pull/7982