FIX: try to fix Flaky test

- wondering if there is just a precision error with ubuntu old CI, and if so, just pushing the visual angle value to be far above .52 (the threshold for warngin) will assure that the warning is thrown across all systems.

mne/preprocessing/eyetracking/tests/test_eyetracking.py

@@ -52,7 +52,7 @@ def test_convert_units(eyetrack_raw, eyetrack_cal):
 
     with pytest.raises(UserWarning, match="Some visual angle values"):
         cal_tmp = cal.copy()
-        cal_tmp["screen_distance"] = 0.3
+        cal_tmp["screen_distance"] = 0.1
         raw_tmp = raw.copy()
         raw_tmp._data[0, :10] = 1900  # gaze to extremity of screen
         mne.preprocessing.eyetracking.convert_units(raw_tmp, cal_tmp, "radians")