fix: Add flaky decorator to test

* TO mitigate failures occurring due to non-deterministic order and
  number of OpenTelemetry spans being exported: open-telemetry/opentelemetry-python#4210

noxfile.py

@@ -47,7 +47,9 @@
 UNIT_TEST_EXTERNAL_DEPENDENCIES: List[str] = []
 UNIT_TEST_LOCAL_DEPENDENCIES: List[str] = []
 UNIT_TEST_DEPENDENCIES: List[str] = []
-UNIT_TEST_EXTRAS: List[str] = []
+UNIT_TEST_EXTRAS: List[str] = [
+    "flaky",
+]
 UNIT_TEST_EXTRAS_BY_PYTHON: Dict[str, List[str]] = {}
 
 SYSTEM_TEST_PYTHON_VERSIONS: List[str] = ["3.12"]

owlbot.py

@@ -335,6 +335,7 @@
     microgenerator=True,
     samples=True,
     cov_level=100,
+    unit_test_extras=["flaky"],
     versions=gcp.common.detect_versions(path="./google", default_first=True),
     unit_test_python_versions=["3.7", "3.8", "3.9", "3.10", "3.11", "3.12"],
     system_test_python_versions=["3.12"],

tests/unit/pubsub_v1/publisher/test_publisher_client.py

@@ -28,6 +28,8 @@
 
 import pytest
 import time
+from flaky import flaky
+from typing import cast, Callable, Any, TypeVar
 
 from opentelemetry import trace
 from google.api_core import gapic_v1
@@ -48,6 +50,9 @@
     PublishMessageWrapper,
 )
 
+C = TypeVar("C", bound=Callable[..., Any])
+typed_flaky = cast(Callable[[C], C], flaky(max_runs=5, min_passes=1))
+
 
 def _assert_retries_equal(retry, retry2):
     # Retry instances cannot be directly compared, because their predicates are
@@ -264,6 +269,7 @@ def test_opentelemetry_publisher_batching_exception(
     sys.version_info < (3, 8),
     reason="Open Telemetry not supported below Python version 3.8",
 )
+@typed_flaky
 def test_opentelemetry_flow_control_exception(creds, span_exporter):
     publisher_options = types.PublisherOptions(
         flow_control=types.PublishFlowControl(