[bugfix] fix no weight_version for aborted samples

Author: zhuzilin

slime/rollout/sglang_rollout.py

@@ -116,7 +116,8 @@ async def generate(args, sample: Sample, sampling_params) -> Sample:
     sample.tokens = sample.tokens + new_response_tokens
     sample.response_length += len(new_response_tokens)
     sample.response += output["text"]
-    sample.weight_versions.append(output["meta_info"]["weight_version"])
+    if "weight_version" in output["meta_info"]:
+        sample.weight_versions.append(output["meta_info"]["weight_version"])
     if sample.rollout_log_probs is None:
         sample.rollout_log_probs = []
     sample.rollout_log_probs += new_response_log_probs