Fix do_merge_lora raises an Exception in transformers v4.37.0

[tisorlawan]

Description

transformers v4.37.0 introduced this change which causes do_merge_lora to raise an exception because the model contains bad generation config, which shown on the stacktrace below.

Traceback (most recent call last):
  File "/home/user/.pyenv/versions/3.10.10/lib/python3.10/site-packages/transformers/generation/configuration_utils.py", line 558, in save_pretrained
    raise ValueError(str([w.message for w in caught_warnings]))
ValueError: [UserWarning('`do_sample` is set to `False`. However, `temperature` is set to `0.9` -- this flag is only used in sample-based generation modes. You should set `do_sample=True` or u
nset `temperature`.'), UserWarning('`do_sample` is set to `False`. However, `top_p` is set to `0.6` -- this flag is only used in sample-based generation modes. You should set `do_sample=True`
or unset `top_p`.')]