[CI] pin NeMo-Skills install to known-good SHA in accuracy_test_runner (#24581)

Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

python/sglang/test/accuracy_test_runner.py

@@ -199,8 +199,11 @@ def _get_nemo_venv() -> Tuple[str, dict]:
             text=True,
         )
 
-    # Install nemo_skills
-    print("Installing nemo_skills...")
+    # Install nemo_skills.
+    # Pinned: NeMo-Skills main after PR #1433 pins litellm==1.83.14 (httpx==0.28.1),
+    # which is unsatisfiable against nemo-run's transitive leptonai dep.
+    nemo_skills_ref = "589294c"
+    print(f"Installing nemo_skills (pinned to {nemo_skills_ref})...")
     pip_result = subprocess.run(
         [
             "uv",
@@ -208,7 +211,7 @@ def _get_nemo_venv() -> Tuple[str, dict]:
             "install",
             "--python",
             f"{_nemo_venv_dir}/venv/bin/python",
-            "git+https://github.com/NVIDIA/NeMo-Skills.git",
+            f"git+https://github.com/NVIDIA/NeMo-Skills.git@{nemo_skills_ref}",
         ],
         capture_output=True,
         text=True,