[Model] [Bugfix] Fix loading of fine-tuned models based on Phi-3-Small

[mgtk77]

We have a fine-tuned model based on Phi-3-Small and loading it fails due to this issue.
It's an official model, created by a team in Microsoft, that handles financial reports.
Model information exists here: https://ai.azure.com/explore/models/financial-reports-analysis/version/2/registry/azureml

The error we get:

...site-packages/vllm/model_executor/models/phi3_small.py", line 477, in load_weights
[rank0]:     param = params_dict[name]
[rank0]: KeyError: 'lm_head.weight'
Loading safetensors checkpoint shards:  75% Completed | 3/4 [00:01<00:00,  2.00it/s]

This fix was verified by successfully loading the model.

We also saw the exact same fix for other models: commandr.py, gemma.py, gpt_bigcode.py and jais.py.

[github-actions]

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[DarkLight1337]

Thanks for fixing!