Fix tests

Author: dstansby

lib/matplotlib/tests/test_colors.py

@@ -666,15 +666,15 @@ def test_TwoSlopeNorm_scaleout_center():
     # test the vmin never goes above vcenter
     norm = mcolors.TwoSlopeNorm(vcenter=0)
     norm([1, 2, 3, 5])
-    assert norm.vmin == 0
+    assert norm.vmin == -5
     assert norm.vmax == 5
 
 
 def test_TwoSlopeNorm_scaleout_center_max():
     # test the vmax never goes below vcenter
     norm = mcolors.TwoSlopeNorm(vcenter=0)
     norm([-1, -2, -3, -5])
-    assert norm.vmax == 0
+    assert norm.vmax == 5
     assert norm.vmin == -5