ci: Migrateunit test for mqtt test to unit test app

- Split mqtt and mqtt5 tests
 - Move common test code to a common component
 - Add necessary python scripts

components/mqtt/test_apps/test_mqtt/pytest_mqtt_ut.py

@@ -0,0 +1,11 @@
+# SPDX-FileCopyrightText: 2023 Espressif Systems (Shanghai) CO LTD
+# SPDX-License-Identifier: Unlicense OR CC0-1.0
+import pytest
+from pytest_embedded import Dut
+
+
+@pytest.mark.esp32
+@pytest.mark.esp32c2
+@pytest.mark.ethernet
+def test_mqtt_client(dut: Dut) -> None:
+    dut.expect_unity_test_output()