BUG: fix bge-reranker-v2-minicpm-layerwise rerank issue

[hustyichi]

The return value of compute_score() in the bge-reranker-v2-minicpm-layerwise model is a two-dimensional array. Currently, an error message only integer scalar arrays can be converted to a scalar index is reported during execution, so additional processing is required

[hustyichi]

Test code

RERANK_MODEL = "BAAI/bge-reranker-v2-minicpm-layerwise"

rerank_model = LayerWiseFlagLLMReranker(RERANK_MODEL, use_fp16=True, device="cuda")

question = "What is the meaning of life?"
passages = [
    "This is a test passage.",
    "This is another test passage.",
]

scores = rerank_model.compute_score(
    [[question, passage] for passage in passages],
    cutoff_layers=[28],
    normalize=True,
)

print(scores)
print(type(scores), type(scores[0]))

The log is:

[[5.225226840386987e-05, 3.120191139396651e-05]]
<class 'list'> <class 'list'>

[qinxuye]

LGTM