Fix non-None constraint noise levels in some constrained test problems (#2241)

Summary:
This was inadvertently overridden / nnot properly set in some constructors.

We currently don't properly test that this attribute is correctly assigned upon instantiation. It's not straightforward to figure out how to easily do this in the current test setup; we can figure that out in a follow-up.

Pull Request resolved: #2241

Reviewed By: SebastianAment

Differential Revision: D54669269

Pulled By: Balandat

fbshipit-source-id: 18248c3851b1235a98f08389215e8e5cc5ffbe74

Author: Balandat

botorch/test_functions/synthetic.py

@@ -848,12 +848,12 @@ def __init__(
             negate: If True, negate the function.
             bounds: Custom bounds for the function specified as (lower, upper) pairs.
         """
-        self.constraint_noise_std = self._validate_constraint_noise(
-            constraint_noise_std
-        )
         SyntheticTestFunction.__init__(
             self, noise_std=noise_std, negate=negate, bounds=bounds
         )
+        self.constraint_noise_std = self._validate_constraint_noise(
+            constraint_noise_std
+        )
 
     def _validate_constraint_noise(
         self, constraint_noise_std
@@ -939,10 +939,12 @@ def __init__(
             negate: If True, negate the function.
             bounds: Custom bounds for the function specified as (lower, upper) pairs.
         """
-        self._validate_constraint_noise(constraint_noise_std)
         Hartmann.__init__(
             self, dim=dim, noise_std=noise_std, negate=negate, bounds=bounds
         )
+        self.constraint_noise_std = self._validate_constraint_noise(
+            constraint_noise_std
+        )
 
     def evaluate_slack_true(self, X: Tensor) -> Tensor:
         return -X.norm(dim=-1, keepdim=True) + 1
@@ -975,10 +977,12 @@ def __init__(
             negate: If True, negate the function.
             bounds: Custom bounds for the function specified as (lower, upper) pairs.
         """
-        self._validate_constraint_noise(constraint_noise_std)
         Hartmann.__init__(
             self, dim=dim, noise_std=noise_std, negate=negate, bounds=bounds
         )
+        self.constraint_noise_std = self._validate_constraint_noise(
+            constraint_noise_std
+        )
 
     def evaluate_slack_true(self, X: Tensor) -> Tensor:
         return -X.pow(2).sum(dim=-1, keepdim=True) + 1