Update unit test with grpc.Future interface

Author: jhamon

tests/unit_grpc/test_grpc_index_upsert.py

@@ -13,9 +13,10 @@
     SparseValues,
 )
 from pinecone.grpc.utils import dict_to_proto_struct
+from grpc import Future as GrpcFuture
 
 
-class MockUpsertDelegate:
+class MockUpsertDelegate(GrpcFuture):
     def __init__(self, upsert_response: UpsertResponse):
         self.response = upsert_response
 
@@ -40,6 +41,9 @@ def running(self):
     def add_done_callback(self, callback):
         pass
 
+    def traceback(self, timeout=None):
+        pass
+
 
 @pytest.fixture
 def expected_vec1(vals1):