test: '{. -> ./mod}/test_util_selinux.py'

Move the 'test_util_selinux.py' test into the module-unittest
subdirectory.

Drop the '__main__' hookup while at it. `python -m unittest --help`
explains how you can run individual tests.

test/mod/__init__.py

@@ -0,0 +1 @@
+# The `unittest` module requires `__init__.py` to discover a directory.

test/mod/test_util_selinux.py

@@ -0,0 +1,42 @@
+#
+# Tests for the 'osbuild.util.selinux' module.
+#
+
+import io
+import unittest
+
+from osbuild.util import selinux
+
+
+class TestObjectStore(unittest.TestCase):
+
+    def test_selinux_config(self):
+        f = io.StringIO()
+        cfg = selinux.parse_config(f)
+        self.assertIsNotNone(cfg)
+        policy = selinux.config_get_policy(cfg)
+        self.assertIsNone(policy)
+
+        example_good = """
+        # This file controls the state of SELinux on the system.
+        # SELINUX= can take one of these three values:
+        #     enforcing - SELinux security policy is enforced.
+        #     permissive - SELinux prints warnings instead of enforcing.
+        #     disabled - No SELinux policy is loaded.
+        SELINUX=enforcing
+        # SELINUXTYPE= can take one of these three values:
+        #     targeted - Targeted processes are protected,
+        #     minimum - Modification of targeted policy.
+        #     mls - Multi Level Security protection.
+        SELINUXTYPE=targeted
+        """
+
+        f = io.StringIO(example_good)
+        cfg = selinux.parse_config(f)
+        self.assertIn('SELINUX', cfg)
+        self.assertIn('SELINUXTYPE', cfg)
+        self.assertEqual(cfg['SELINUX'], 'enforcing')
+        self.assertEqual(cfg['SELINUXTYPE'], 'targeted')
+
+        policy = selinux.config_get_policy(cfg)
+        self.assertEqual(policy, 'targeted')