Add discovery of sensors on DS2409 MicroLan (#43599)

* Add discovery of sensors on DS2409 MicroLan

* Add tests for coupler

* Update tests

* Fix isort

* Clean up

* Move tests to test_sensor.py

Co-authored-by: epenet <6771947+epenet@users.noreply.github.com>
Co-authored-by: Martin Hjelmare <marhje52@gmail.com>

tests/components/onewire/test_entity_owserver.py

@@ -179,6 +179,18 @@ MOCK_DEVICE_SENSORS = {
             },
         ],
     },
+    "1F.111111111111": {
+        "inject_reads": [
+            b"DS2409",  # read device type
+        ],
+        "device_info": {
+            "identifiers": {(DOMAIN, "1F.111111111111")},
+            "manufacturer": "Maxim Integrated",
+            "model": "DS2409",
+            "name": "1F.111111111111",
+        },
+        SENSOR_DOMAIN: [],
+    },
     "22.111111111111": {
         "inject_reads": [
             b"DS1822",  # read device type
@@ -752,3 +764,6 @@ async def test_owserver_setup_valid_device(owproxy, hass, device_id, platform):
             assert state is None
         else:
             assert state.state == expected_sensor["result"]
+            assert state.attributes["device_file"] == expected_sensor.get(
+                "device_file", registry_entry.unique_id
+            )