[BUG] misleading error when extending an unknown service

[luciangabor]

Description

The error states that the service that extends an unknown service is the one that is not found. The error should properly name the unknown service.

Steps To Reproduce

$ docker compose -f - config <<EOF
services:
  known:
    extends: unknown
    image: image
EOF
cannot extend service "known" in -: service not found

Compose Version

Docker Compose version v2.24.6

Docker Environment

No response

Anything else?

No response