test: use pytest for examples/custom_bootloader

examples/custom_bootloader/bootloader_override/pytest_custom_bootloader_override.py

@@ -0,0 +1,21 @@
+# SPDX-FileCopyrightText: 2021 Espressif Systems (Shanghai) CO LTD
+# SPDX-License-Identifier: CC0-1.0
+
+import pytest
+from pytest_embedded.dut import Dut
+from pytest_embedded_idf.app import IdfApp
+
+
+@pytest.mark.esp32
+@pytest.mark.esp32s2
+@pytest.mark.esp32c3
+@pytest.mark.generic
+def test_custom_bootloader_impl_example(app: IdfApp, dut: Dut) -> None:
+    # Expect to read a message from the custom bootloader
+    # This message is defined in the Kconfig file, retrieve it while deleting
+    # leading and trailing quotes (")
+    welcome_message = app.sdkconfig['EXAMPLE_BOOTLOADER_WELCOME_MESSAGE']
+    dut.expect_exact(welcome_message)
+
+    # Expect to read a message from the user application
+    dut.expect_exact('Application started!')