chore: use gapic-generator-python 1.0.0 (#54)

* chore: use gapic-generator-python 1.0.0

PiperOrigin-RevId: 451250442

Source-Link: googleapis/googleapis@cca5e81

Source-Link: googleapis/googleapis-gen@0b219da
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packages/google-cloud-certificate-manager/tests/unit/gapic/certificate_manager_v1/test_certificate_manager.py

@@ -13,9 +13,17 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 #
-import math
 import os
 
+# try/except added for compatibility with python < 3.8
+try:
+    from unittest import mock
+    from unittest.mock import AsyncMock
+except ImportError:
+    import mock
+
+import math
+
 from google.api_core import (
     future,
     gapic_v1,
@@ -37,7 +45,6 @@
 from google.protobuf import timestamp_pb2  # type: ignore
 import grpc
 from grpc.experimental import aio
-import mock
 from proto.marshal.rules.dates import DurationRule, TimestampRule
 import pytest