CI: Prepare mqtt app test for QEMU tests

Adds qemu configuration
Generalize the get_dut() to enable choosing DUT class per configuration

tools/test_apps/protocols/mqtt/publish_connect_test/app_test.py

@@ -247,7 +247,7 @@ def test_app_protocol_mqtt_publish_connect(env, extra_data):
       2. connect to uri specified in the config
       3. send and receive data
     """
-    dut1 = env.get_dut('mqtt_publish_connect_test', 'tools/test_apps/protocols/mqtt/publish_connect_test', dut_class=ttfw_idf.ESP32DUT)
+    dut1 = env.get_dut('mqtt_publish_connect_test', 'tools/test_apps/protocols/mqtt/publish_connect_test')
     # check and log bin size
     binary_file = os.path.join(dut1.app.binary_path, 'mqtt_publish_connect_test.bin')
     bin_size = os.path.getsize(binary_file)

tools/test_apps/protocols/mqtt/publish_connect_test/sdkconfig.qemu

@@ -17,3 +17,7 @@ CONFIG_EXAMPLE_BROKER_CERTIFICATE_OVERRIDE="${EXAMPLE_MQTT_BROKER_CERTIFICATE}"
 CONFIG_MBEDTLS_HARDWARE_AES=n
 CONFIG_MBEDTLS_HARDWARE_MPI=n
 CONFIG_MBEDTLS_HARDWARE_SHA=n
+CONFIG_ETH_USE_SPI_ETHERNET=n
+CONFIG_EXAMPLE_CONNECT_WIFI=n
+CONFIG_ESP_TLS_INSECURE=y
+CONFIG_ESP_TLS_SKIP_SERVER_CERT_VERIFY=y