re-add missing fixture

tests/test_detection.py

@@ -1,4 +1,5 @@
 import shutil
+from pathlib import Path
 from unittest.mock import patch
 
 import numpy as np
@@ -11,6 +12,17 @@ import dopt_sensor_anomalies.types as t
 from dopt_sensor_anomalies import constants, errors
 
 
+@pytest.fixture(scope="module")
+def single_img_path() -> Path:
+    img_folder = Path(__file__).parent / "_img"
+    if not img_folder.exists():
+        raise FileNotFoundError("Img path not existing")
+    img_paths = tuple(img_folder.glob("*_12.bmp"))
+    if not img_paths:
+        raise ValueError("No images found")
+    return img_paths[0]
+
+
 def test_midpoint():
     ptA = np.array([1.0, 2.0])
     ptB = np.array([3.0, 4.0])