[CI] Fix neuron CI and run offline tests (#11779)

Signed-off-by: Liangfu Chen <liangfc@amazon.com>

examples/offline_inference_neuron.py

@@ -1,12 +1,5 @@
-import os
-
 from vllm import LLM, SamplingParams
 
-# creates XLA hlo graphs for all the context length buckets.
-os.environ['NEURON_CONTEXT_LENGTH_BUCKETS'] = "128,512,1024,2048"
-# creates XLA hlo graphs for all the token gen buckets.
-os.environ['NEURON_TOKEN_GEN_BUCKETS'] = "128,512,1024,2048"
-
 # Sample prompts.
 prompts = [
     "Hello, my name is",
@@ -26,8 +19,8 @@ llm = LLM(
     # Currently, this is a known limitation in continuous batching support
     # in transformers-neuronx.
     # TODO(liangfu): Support paged-attention in transformers-neuronx.
-    max_model_len=2048,
-    block_size=2048,
+    max_model_len=1024,
+    block_size=1024,
     # The device can be automatically detected when AWS Neuron SDK is installed.
     # The device argument can be either unspecified for automated detection,
     # or explicitly assigned.