fix tests for extractor

Author: TjarkMiener

src/ctapipe/image/tests/test_extractor.py

@@ -929,7 +929,7 @@ def is_flashcam(tel_id):
 
                 waveforms = event.r1.tel[tel_id].waveform
                 selected_gain_channel = np.zeros(waveforms.shape[-2], dtype=np.int64)
-                broken_pixels = event.calibration.tel[tel_id].dl1.outlier_mask
+                broken_pixels = event.calibration.tel[tel_id].outlier_mask
 
                 dl1 = extractor(waveforms, tel_id, selected_gain_channel, broken_pixels)
                 assert dl1.is_valid