fix(cicd): treat branch follower budgets as advisory

scripts/native/cicd/controller-one-shot.sh

@@ -4,7 +4,7 @@ set -eu
 cd /work
 rm -rf /work/unidesk
 started_at=$(date -Iseconds)
-echo "branch-follower one-shot started ${started_at}"
+echo "branch-follower one-shot started ${started_at}" >&2
 
 /etc/unidesk-cicd-branch-follower/sync-source.sh \
   "${UNIDESK_CONTROLLER_SOURCE_REPOSITORY}" \
@@ -18,4 +18,4 @@ cd /work/unidesk
 
 "$@"
 
-echo "branch-follower one-shot finished $(date -Iseconds)"
+echo "branch-follower one-shot finished $(date -Iseconds)" >&2