Fix typos when moving hardware test suit to new test env structure

tests/hardware_specific_tests/picamera2/cam_test_utils.py

@@ -34,4 +34,4 @@ def camera_test_client(settings_folder: Optional[str] = None):
         temporary directory will be used as the settings folder.
     """
     with camera_test_env(settings_folder=settings_folder) as env:
-        return env.get_thing_client("camera")
+        yield env.get_thing_client("camera")

tests/hardware_specific_tests/picamera2/conftest.py

@@ -4,18 +4,18 @@ import pytest
 
 import labthings_fastapi as lt
 
-from .cam_test_utils import camera_test_client_and_server
+from .cam_test_utils import camera_test_env
 
 
 @pytest.fixture
 def picamera_test_env() -> lt.ThingClient:
     """Initialise a test environment with only a StreamingPiCamera2 Thing."""
-    with camera_test_client_and_server() as env:
+    with camera_test_env() as env:
         yield env
 
 
 @pytest.fixture
 def picamera_client() -> lt.ThingClient:
     """Initialise a test picamera_client (in a LabThings test env)."""
-    with camera_test_client_and_server() as env:
-        return env.get_thing_client["camera"]
+    with camera_test_env() as env:
+        yield env.get_thing_client("camera")

tests/hardware_specific_tests/picamera2/test_calibration.py

@@ -10,7 +10,7 @@ from .cam_test_utils import camera_test_client
 
 def test_calibration(picamera_test_env):
     """Check that full auto calibrate completes and set the expected values."""
-    picamera_client, server = picamera_test_env.get_thing_client["camera"]
+    picamera_client = picamera_test_env.get_thing_client("camera")
     picamera_thing = picamera_test_env.get_thing_by_type(StreamingPiCamera2)
     # Check the calibration_required property used by the calibration wizard
     assert picamera_thing.calibration_required