message: Fix flaky auto_mixed_precision_test.cc.
  AutoMixedPrecisionTest.SoftmaxOp would fail ~1% of the time, and AutoMixedPrecisionTest.LogSoftmaxOp would fail ~0.1% of the time.
diff: @@ -1020,7 +1020,7 @@ TEST_F(AutoMixedPrecisionTest, Log1pOp) {
  TEST_F(AutoMixedPrecisionTest, LogSoftmaxOp) {
  TestSimpleUnaryGrayOp(
  - -8, 8, -1, 5.0e-3,
  + -8, 8, -1, 1.0e-2,
  [](const tensorflow::Scope& scope, Output input) -> Output {
  return ops::LogSoftmax(scope, input);
  });
  @@ -1043,9 +1043,8 @@ TEST_F(AutoMixedPrecisionTest, SigmoidOp) {
  }
  TEST_F(AutoMixedPrecisionTest, SoftmaxOp) {
  - GTEST_SKIP() << "b/142826443. Reenable once fixed.";
  TestSimpleUnaryGrayOp(
  - -8, 8, 1.0e-3, -1,
  + -8, 8, 2.0e-3, -1,
  [](const tensorflow::Scope& scope, Output input) -> Output {
  return ops::Softmax(scope, input);
  });
  