Tighten test_normal_scalar bound (#5366)

pymc/tests/test_sampling.py

@@ -508,7 +508,7 @@ def test_normal_scalar(self):
             assert ppc["a"].shape == (nchains * ndraws,)
             # mu's standard deviation may have changed thanks to a's observed
             _, pval = stats.kstest(ppc["a"] - trace["mu"], stats.norm(loc=0, scale=1).cdf)
-            assert pval > 0.001
+            assert pval > 0.01
 
         # size argument not introduced to fast version [2019/08/20:rpg]
         with model: