tests: add more integration tests for core tools.

tests/bats/systemd-cat.bats

@@ -0,0 +1,22 @@
+#!/usr/bin/env bats
+# apparmor.d - Full set of apparmor profiles
+# Copyright (C) 2024 Alexandre Pujol <alexandre@pujol.io>
+# SPDX-License-Identifier: GPL-2.0-only
+
+load common
+
+setup_file() {
+    aa_setup
+}
+
+# bats test_tags=systemd-cat
+@test "systemd-cat: Write the output of the specified command to the journal (both output streams are captured)" {
+    systemd-cat pwd
+    aa_check
+}
+
+# bats test_tags=systemd-cat
+@test "systemd-cat: Write the output of a pipeline to the journal (`stderr` stays connected to the terminal)" {
+    echo apparmor.d-test-suite | systemd-cat
+    aa_check
+}