test: Fix shellcheck warnings

Signed-off-by: Jacques de Laval <jacques@de-laval.se>

test/test_start_stop_service/test.sh

@@ -11,8 +11,8 @@ say 'Reload Finit'
 texec kill -SIGHUP 1
 sleep 1
 
-service_pids=( $(texec pgrep -P 1) )
-assert 'One service is running' ${#service_pids[@]} -eq 1
+service_pids=$(texec pgrep -P 1 | wc -l)
+assert 'One service is running' "$service_pids" -eq 1
 
 say 'Remove the service'
 texec sh -c 'echo > /etc/finit.conf'
@@ -21,8 +21,8 @@ say 'Reload Finit'
 texec kill -SIGHUP 1
 sleep 1
 
-service_pids=( $(texec pgrep -P 1) )
-assert 'Zero services are running' ${#service_pids[@]} -eq 0
+service_pids=$(texec pgrep -P 1 | wc -l)
+assert 'Zero services are running' "$service_pids" -eq 0
 
 # Teardown
 rm -f test_root/bin/service.sh