add pytest for example deep sleep wake stub

examples/system/deep_sleep_wake_stub/pytest_deep_sleep_wake_stub.py

@@ -0,0 +1,28 @@
+# SPDX-FileCopyrightText: 2021-2022 Espressif Systems (Shanghai) CO LTD
+# SPDX-License-Identifier: CC0-1.0
+
+import logging
+import time
+
+import pytest
+from pytest_embedded import Dut
+
+
+@pytest.mark.esp32
+@pytest.mark.esp32s2
+@pytest.mark.esp32s3
+@pytest.mark.esp32c3
+@pytest.mark.generic
+@pytest.mark.parametrize('config', ['default',], indirect=True)
+def test_deep_sleep_wake_stub(config: str, dut: Dut) -> None:
+    if config == 'default':
+        dut.expect_exact('Enabling timer wakeup, 10s', timeout=10)
+        dut.expect_exact('Entering deep sleep', timeout=10)
+
+        start_sleep = time.time()
+        logging.info('Waiting for wakeup...')
+        dut.expect_exact('wake stub: going to deep sleep')
+
+        sleep_time = time.time() - start_sleep
+        logging.info('Host measured sleep time at {:.2f}s'.format(sleep_time))
+        assert 8 < sleep_time < 12  # note: high tolerance as measuring time on the host may have some timing skew