test: move TEST-05-RLIMITS setup to static files

The test currently fails in the check for LimitNOFILESoft/LimitNOFILE. I see
default values there. This doesn't seem to be related to the changes in the
test suite, but rather to the recent changes to pid1.

test/units/testsuite-05.service

@@ -0,0 +1,6 @@
+[Unit]
+Description=TEST-05-RLIMITS
+
+[Service]
+ExecStart=/usr/lib/systemd/tests/testdata/units/%N.sh
+Type=oneshot

test/units/testsuite-05.sh

@@ -0,0 +1,25 @@
+#!/usr/bin/env bash
+set -x
+set -e
+set -o pipefail
+
+P=/run/systemd/system.conf.d
+mkdir $P
+
+cat >$P/rlimits.conf <<EOF
+[Manager]
+DefaultLimitNOFILE=10000:16384
+EOF
+
+systemctl daemon-reload
+
+[[ "$(systemctl show --value -p DefaultLimitNOFILESoft)" = "10000" ]]
+[[ "$(systemctl show --value -p DefaultLimitNOFILE)" = "16384" ]]
+
+[[ "$(systemctl show --value -p LimitNOFILESoft testsuite-05.service)" = "10000" ]]
+[[ "$(systemctl show --value -p LimitNOFILE testsuite-05.service)" = "16384" ]]
+
+systemd-run --wait -t bash -c '[[ "$(ulimit -n -S)" = "10000" ]]'
+systemd-run --wait -t bash -c '[[ "$(ulimit -n -H)" = "16384" ]]'
+
+touch /testok