fix: make .runpod/tests.json hub tests pass on CUDA 13.0 (#299)

Three coupled fixes verified end-to-end on a private fork
(TimPietruskyRunPod/worker-vllm v0.1.3 → both hub tests passing):

1. tests.json allowedCudaVersions: 12.x → 13.0
   The Dockerfile and hub.json moved to CUDA 13.0 in v2.20.0
   (#288, #289), but tests.json was still pinned to 12.5–12.9, so
   the test pod was scheduled on a GPU with driver < 13.0 and
   container init failed at the nvidia-container-cli hook with
   "unsatisfied condition: cuda>=13.0".

2. requirements.txt kernels<0.15
   huggingface/kernels v0.15.1 tightened LayerRepository to require
   a revision or version argument
   (https://github.com/huggingface/kernels/pull/544). transformers
   >=5 still constructs LayerRepository(repo_id=..., layer_name=...)
   without either, so worker import raised ValueError during
   `from transformers import ...`. 0.14.1 is the last safe release.

3. tests.json timeout 30000 → 300000
   vLLM cold start (torch.compile + FlashInfer warmup) on RTX 4090
   for SmolLM2-135M takes ~60–70s before the first request can be
   served. The previous 30s per-test timeout fired before the
   worker came up, producing "context cancelled or timed out:
   context deadline exceeded" for every test even when the worker
   was healthy. 300s gives enough headroom for cold start + the
   actual inference call.

Refs: DR-1161

.runpod/tests.json

@@ -5,7 +5,7 @@
       "input": {
         "prompt": "Write a short poem about artificial intelligence."
       },
-      "timeout": 30000
+      "timeout": 300000
     },
     {
       "name": "openai_messages_test",
@@ -26,7 +26,7 @@
           "temperature": 0.1
         }
       },
-      "timeout": 30000
+      "timeout": 300000
     }
   ],
   "config": {
@@ -38,6 +38,6 @@
         "value": "HuggingFaceTB/SmolLM2-135M-Instruct"
       }
     ],
-    "allowedCudaVersions": ["12.9", "12.8", "12.7", "12.6", "12.5"]
+    "allowedCudaVersions": ["13.0"]
   }
 }

builder/requirements.txt

@@ -11,5 +11,5 @@ pydantic-settings
 hf-transfer
 transformers>=5
 bitsandbytes>=0.45.0
-kernels
+kernels<0.15
 torch-c-dlpack-ext