fix type error message regex for py 3.9 (#2142)

Summary:
Pull Request resolved: #2142

py3.9 does not include the class name in the error message

Reviewed By: esantorella

Differential Revision: D51983682

fbshipit-source-id: b021afd10fdd9b408c4f11ca8a0cc2fc91702cb4

Author: sdaulton

test/acquisition/test_monte_carlo.py

@@ -816,10 +816,7 @@ def test_q_simple_regret_constraints(self):
         samples = torch.zeros(2, 2, 1, device=self.device, dtype=torch.double)
         samples[0, 0, 0] = 1.0
         mm = MockModel(MockPosterior(samples=samples))
-        regex = (
-            r"qSimpleRegret\.__init__\(\) got an unexpected keyword argument "
-            r"'constraints'"
-        )
+        regex = r"__init__\(\) got an unexpected keyword argument 'constraints'"
         with self.assertRaisesRegex(TypeError, regex):
             qSimpleRegret(model=mm, constraints=[lambda Y: Y[..., 0]])