si-standard-link: always return transition error if activation fails

Avoids having the session item in an invalid state.
7 jobs for session-item-fixes in 24 minutes and 11 seconds (queued for 17 seconds)
Status Name Job ID Coverage
  Container
passed container_fedora #16168025

00:00:30

passed container_ubuntu #16168026

00:00:36

 
  Build
passed build_on_fedora_no_docs #16168028

00:01:05

passed build_on_fedora_with_docs #16168027

00:19:15

passed build_on_ubuntu_no_gir #16168030

00:01:03

passed build_on_ubuntu_with_gir #16168029

00:16:39

 
  Analysis
passed shellcheck #16168031

00:04:17