Fix asyncio sglang use

[pseudotensor]

For error:

    output = await self._agenerate_helper(
  File "/home/ubuntu/miniconda3/envs/h2ogpt/lib/python3.10/site-packages/langchain_core/language_models/llms.py", line 882, in _agenerate_helper
    raise e
  File "/home/ubuntu/miniconda3/envs/h2ogpt/lib/python3.10/site-packages/langchain_core/language_models/llms.py", line 866, in _agenerate_helper
    await self._agenerate(
  File "/home/ubuntu/h2ogpt/src/gpt_langchain.py", line 596, in _agenerate
    texts = await asyncio.gather(*tasks)
  File "/home/ubuntu/h2ogpt/src/gpt_langchain.py", line 613, in _agenerate_one
    return await self._acall(prompt, stop=stop, run_manager=run_manager, **kwargs) \
  File "/home/ubuntu/h2ogpt/src/gpt_langchain.py", line 1731, in _acall
    response = self.setup_call(prompt)
  File "/home/ubuntu/h2ogpt/src/gpt_langchain.py", line 1629, in setup_call
    responses = asyncio.run(self.get_many(url, pload))
  File "/home/ubuntu/miniconda3/envs/h2ogpt/lib/python3.10/asyncio/runners.py", line 33, in run
    raise RuntimeError(
RuntimeError: asyncio.run() cannot be called from a running event loop

for this code:

responses = asyncio.run(self.get_many(url, pload))