bios: main now returns None on success and 1 any error

src/amd_debug/bios.py

diff --git a/src/amd_debug/bios.py b/src/amd_debug/bios.py
index d2b1ffc..a5ea8b9 100644
--- a/src/amd_debug/bios.py
+++ b/src/amd_debug/bios.py
@@ -122,7 +122,7 @@
     return args
 
 
-def main():
+def main() -> None|int:
     """Main function"""
     args = parse_args()
     ret = False
@@ -135,4 +135,6 @@
     elif args.command == "version":
         print(version())
     show_log_info()
-    return ret
+    if ret is False:
+        return 1
+    return

src/test_bios.py

diff --git a/src/test_bios.py b/src/test_bios.py
index efe2d3c..c780ed4 100644
--- a/src/test_bios.py
+++ b/src/test_bios.py
@@ -194,7 +194,7 @@
         mock_amd_bios.assert_called_once_with(None, True)
         mock_app.set_tracing.assert_called_once_with(True)
         mock_show_log_info.assert_called_once()
-        self.assertTrue(result)
+        self.assertIsNone(result)
 
     @patch("amd_debug.bios.AmdBios")
     @patch("amd_debug.bios.parse_args")
@@ -217,7 +217,7 @@
         mock_amd_bios.assert_called_once_with("test.log", True)
         mock_app.run.assert_called_once()
         mock_show_log_info.assert_called_once()
-        self.assertTrue(result)
+        self.assertIsNone(result)
 
     @patch("amd_debug.bios.parse_args")
     @patch("amd_debug.bios.version")
@@ -235,7 +235,7 @@
         mock_parse_args.assert_called_once()
         mock_version.assert_called_once()
         mock_show_log_info.assert_called_once()
-        self.assertEqual(result, False)
+        self.assertEqual(result, 1)
 
     @patch("amd_debug.bios.parse_args")
     @patch("amd_debug.bios.show_log_info")
@@ -247,4 +247,4 @@
 
         mock_parse_args.assert_called_once()
         mock_show_log_info.assert_called_once()
-        self.assertFalse(result)
+        self.assertEqual(result, 1)