Adds SecureToken to currently logged-in user. Prompts for password of SecureToken admin (gets SecureToken Admin Username from Jamf Pro script parameter) and logged-in user.
This workflow is required to authorize programmatically-created user accounts (that were not already explicitly given a SecureToken) to enable or use FileVault and unlock disk encryption on APFS-formatted startup volumes.
sysadminctlSecureToken syntax discovered and formalized in MacAdmins Slack #filevault.