Online testing uses different directory; fixing in helper tests.

Author: Cameron-Van-Eck

tests/helper_test.py

@@ -104,6 +104,8 @@ def setUp(self):
             shutil.rmtree(TEST_PATH / "simdata")
 
         (TEST_PATH / "simdata").mkdir(parents=True)
+        (TEST_PATH / "simdata/1D").mkdir(parents=True)
+        (TEST_PATH / "simdata/3D").mkdir(parents=True)
 
         N_chan = 288
         self.freq_arr = np.linspace(800e6, 1088e6, num=N_chan)