refactor test_expert_load_balancer to keep the ut code style This PR also fixed the break change from https://github.com/vllm-project/vllm/pull/16188/files#diff-e2942ece30a5c580437694ffb964bfc664b510c59244c08e5921b8f5cefb4280 This is just a quick fix. We'll support embedding on V1 later Closes: https://github.com/vllm-project/vllm-ascend/issues/1299 Signed-off-by: wangxiyuan <wangxiyuan1007@gmail.com>