[Bugfix] Update starcoder2 to remap k/v scale names for kv_cache quantization

[dsikka]

Summary:

• In response to the following bug: KeyError: 'model.layers.0.self_attn.k_scale' llm-compressor#967
• Update to remap the k/v scale names so that they can be loaded post kv cache quantization

[github-actions]

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