Updates access_policy_version setter and unittest

Author: chalmerlowe

google/cloud/bigquery/dataset.py

@@ -988,7 +988,7 @@ def access_policy_version(self):
     def access_policy_version(self, value):
         if not isinstance(value, int) and value is not None:
             raise ValueError("Pass an integer, or None")
-        self._properties[self._PROPERTY_TO_API_FIELD["access_policy_version"]] = value
+        self._properties["accessPolicyVersion"] = value
 
     @classmethod
     def from_string(cls, full_dataset_id: str) -> "Dataset":

tests/unit/test_dataset.py

@@ -1428,6 +1428,8 @@ def test_access_policy_version_valid_input(self):
         dataset = self._make_one(self.DS_REF)
         # Valid inputs for access_policy_version are currently
         # ints 1, 2, 3, and None
+        # We rely upon the BQ backend to validate acceptable integer
+        # values, rather than perform that validation in the client.
         for expected in [1, 2, 3, None]:
             # set property using setter and integer
             dataset.access_policy_version = expected