[Doc] Tutorial of ml_Inference processor with Cohere Rerank model seems wrong

[ylwu-amzn]

The ML inference processor looks not correct in https://github.com/opensearch-project/ml-commons/blob/main/docs/tutorials/ml_inference/rerank/ml_Inference_with_Cohere_Rerank_model.md#1-create-reranking-pipeline

        "input_map": {
          "documents": "fact_description",
          "query": "_request.ext.query_context.query_text",
          "top_n": "_request.ext.query_context.top_n"
        },
        "output_map": {
          "relevance_score": "results[*].relevance_score",
          "description": "results[*].document.text"
        },

The input/output map should be array of objects like

        "input_map": [
           {
             "documents": "fact_description",
             "query": "_request.ext.query_context.query_text",
             "top_n": "_request.ext.query_context.top_n"
           }
         ],
        "output_map": [
           {
             "relevance_score": "results[*].relevance_score",
             "description": "results[*].document.text"
           }
        ],