tighten test_spectral_mixture_gp_mean_abs_error bound (#1866)

Co-authored-by: Geoff Pleiss <[email protected]>

Author: austereantelope

test/examples/test_spectral_mixture_gp_regression.py

@@ -101,7 +101,7 @@ def test_spectral_mixture_gp_mean_abs_error(self, empspect=False):
 
         # The spectral mixture kernel should be trivially able to
         # extrapolate the sine function.
-        self.assertLess(mean_abs_error.squeeze().item(), 0.2)
+        self.assertLess(mean_abs_error.squeeze().item(), 0.02)
 
 
 if __name__ == "__main__":