[tests] Fix fork() test.
process.poll() may return 0.
@@ -43,7 +43,7 @@ def test_fork_child_process_is_not_orphaned(env: LlvmEnv):
fkd.close()
# Check that the service has been killed.
- assert process.poll()
+ assert process.poll() is not None
finally:
fkd.close()
