tests: fix TEST-03-JOBS

We have

JOB UNIT                     TYPE  STATE
  1 testsuite.target         start waiting
 81 end.service              start waiting
187 sleep.service            start waiting
136 hello.service            start waiting
 82 testsuite.service        start running
135 hello-after-sleep.target start waiting

sometimes

1 files changed, 5 insertions, 2 deletions

diff --git a/test/TEST-03-JOBS/test-jobs.sh b/test/TEST-03-JOBS/test-jobs.sh
index 42d475fe2f..4252a9a75d 100755
--- a/test/TEST-03-JOBS/test-jobs.sh
+++ b/test/TEST-03-JOBS/test-jobs.sh
@@ -4,9 +4,12 @@
 # installed job.
 
 systemctl start --no-block hello-after-sleep.target
-# sleep is now running, hello/start is waiting. Verify that:
+
 systemctl list-jobs > /root/list-jobs.txt
-grep 'sleep\.service.*running' /root/list-jobs.txt || exit 1
+while ! grep 'sleep\.service.*running' /root/list-jobs.txt; do
+    systemctl list-jobs > /root/list-jobs.txt
+done
+
 grep 'hello\.service.*waiting' /root/list-jobs.txt || exit 1
 
 # This is supposed to finish quickly, not wait for sleep to finish.