[vllm] feat: make seed configurable and different among replicas (verl-project#5181)

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Author: vermouth1992

verl/workers/rollout/vllm_rollout/vllm_async_server.py

@@ -282,7 +282,7 @@ async def launch_server(self, master_address: str = None, master_port: int = Non
             "gpu_memory_utilization": self.config.gpu_memory_utilization,
             "disable_log_stats": self.config.disable_log_stats,
             "tensor_parallel_size": self.config.tensor_model_parallel_size,
-            "seed": self.replica_rank,
+            "seed": self.replica_rank + self.config.get("seed", 0),
             "override_generation_config": json.dumps(override_generation_config),
             "quantization": quantization,
             "hf_overrides": hf_overrides,