fixed 3D lungwave for test suite

Author: mrodrig6

examples/3D_lungwave/case.py

@@ -102,7 +102,7 @@
             "a_x": 4.0e00,
             "x_a": -5.0,
             "x_b": 5.0,
-            "loops_x": 0,
+            #"loops_x": 0,
             "dt": dt,
             "t_step_start": tstart,
             "t_step_stop": tstop,