TST: skip broken test

This test only over passed due to an error arising from a bug
in numpy's divmod being fixed (numpy/numpy#6127).

See #5950

lib/matplotlib/tests/test_axes.py

@@ -21,7 +21,8 @@
 import warnings
 
 import matplotlib
-from matplotlib.testing.decorators import image_comparison, cleanup
+from matplotlib.testing.decorators import (image_comparison, cleanup,
+                                           knownfailureif)
 import matplotlib.pyplot as plt
 import matplotlib.markers as mmarkers
 from numpy.testing import assert_allclose, assert_array_equal
@@ -86,6 +87,7 @@ def test_formatter_ticker():
     ax.autoscale_view()
 
 
+@knownfailureif(tuple(map(int, np.__version__.split('.'))) >= (1, 11, 0))
 @image_comparison(baseline_images=["formatter_large_small"])
 def test_formatter_large_small():
     # github issue #617, pull #619