[service] Fix benchmark test in python service.
@@ -105,7 +105,7 @@ class CompilerGymService(CompilerGymServiceServicerStub): # pragma: no cover
with self.sessions_lock, exception_to_grpc_status(context):
# If a benchmark definition was provided, add it.
- if request.benchmark.program:
+ if request.benchmark.HasField("program"):
self.benchmarks[request.benchmark.uri] = request.benchmark
# Lookup the requested benchmark.
