test: remove exit 0 at the end

We don't need that at the end, as it will always exit with 0 if
everything is okey.

test/TEST-03-JOBS/test-jobs.sh

@@ -50,4 +50,3 @@ systemctl stop --job-mode=replace-irreversibly unstoppable.service || exit 1
 systemctl start unstoppable.service || exit 1
 
 touch /testok
-exit 0

test/TEST-04-JOURNAL/test-journal.sh

@@ -60,4 +60,3 @@ systemctl stop forever-print-hola
 [[ ! -f "/i-lose-my-logs" ]]
 
 touch /testok
-exit 0

test/TEST-05-RLIMITS/test-rlimits.sh

@@ -14,4 +14,3 @@ set -o pipefail
 [[ "$(ulimit -n -H)" = "16384" ]]
 
 touch /testok
-exit 0

test/TEST-06-SELINUX/test-selinux-checks.sh

@@ -10,4 +10,3 @@ runcon -t systemd_test_reload_t systemctl reload hola
 runcon -t systemd_test_stop_t systemctl stop hola
 
 touch /testok
-exit 0