feat(bigquery): refactor class imports as it moved to new file

Author: HemangChothani

bigquery/google/cloud/bigquery/dataset.py

@@ -24,7 +24,7 @@
 from google.cloud.bigquery.model import ModelReference
 from google.cloud.bigquery.routine import RoutineReference
 from google.cloud.bigquery.table import TableReference
-from google.cloud.bigquery.table import EncryptionConfiguration
+from google.cloud.bigquery.encryption_configuration import EncryptionConfiguration
 
 
 def _get_table_reference(self, table_id):
@@ -577,7 +577,7 @@ def labels(self, value):
 
     @property
     def default_encryption_configuration(self):
-        """google.cloud.bigquery.table.EncryptionConfiguration: Custom
+        """google.cloud.bigquery.encryption_configuration.EncryptionConfiguration: Custom
         encryption configuration for all tables in the dataset.
 
         Custom encryption configuration (e.g., Cloud KMS keys) or :data:`None`

bigquery/tests/unit/test_dataset.py

@@ -568,7 +568,9 @@ def test_to_api_repr_w_custom_field(self):
         self.assertEqual(resource, exp_resource)
 
     def test_default_encryption_configuration_setter(self):
-        from google.cloud.bigquery.table import EncryptionConfiguration
+        from google.cloud.bigquery.encryption_configuration import (
+            EncryptionConfiguration,
+        )
 
         dataset = self._make_one(self.DS_REF)
         encryption_configuration = EncryptionConfiguration(