enable external launcher

Signed-off-by: wangli <wangli858794774@gmail.com>

Author: Potabk

.github/workflows/_e2e_test.yaml

@@ -172,7 +172,7 @@ jobs:
           pytest -sv tests/e2e/multicard/test_data_parallel.py
           pytest -sv tests/e2e/multicard/test_expert_parallel.py
           # external_launcher test is not stable enough. Fix it later
-          # pytest -sv tests/e2e/multicard/test_external_launcher.py
+          pytest -sv tests/e2e/multicard/test_external_launcher.py
           pytest -sv tests/e2e/multicard/test_fused_moe_allgather_ep.py
           #pytest -sv tests/e2e/multicard/test_ilama_lora_tp2.py