CORD-3012 cause Chameleon to timeout if GetSchema operation is stuck

Change-Id: I5e92382b14f231680d26daacce358d55d92e061e
diff --git a/grpc_client/grpc_client.py b/grpc_client/grpc_client.py
index 316970b..9e7987c 100644
--- a/grpc_client/grpc_client.py
+++ b/grpc_client/grpc_client.py
@@ -201,7 +201,7 @@
         assert isinstance(self.channel, grpc.Channel)
         stub = SchemaServiceStub(self.channel)
         # try:
-        schemas = stub.GetSchema(Empty())
+        schemas = stub.GetSchema(Empty(), timeout=120)
         # except _Rendezvous, e:
         #     if e.code == grpc.StatusCode.UNAVAILABLE:
         #