security/py-service_identity: Mark DEPRECATED and set EXPIRATION_DATE to 2024-01-31

• While I'm here, fix path (devel/ -> security/)

PR: 275167
Reported by: John Hein <jcfyecrayz@liamekaens.com>
Approved by: Axel Rau <axel.rau@chaos1.de> (maintainer)