[Tiny] renaming a field name (init_lora_weights)

[optas]

Description

Renames the PEFT parameter init_lora_weights to lora_init_weights to be name-wise more aligned with the rest of Oumi PEFT parameters. init_lora_weights is how HF names this.

@wizeng23 please note that the file you added adapter_config still lists it as init_lora_weights. I think that is OK since that seems to be a file testing HF and not Oumi directly (e.g., it also contains fields like rslora, use_dora etc.)

Related issues

Fixes # (issue)

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