docs: Partial integration update for cohere embeddings (#25250)

This can be finished after the following issue is resolved:

langchain-ai/langchain-cohere#81

Related to: #24856

```json
[
   {
      "provider": "cohere",
      "js":  true,
      "local": false,
     "serializable": false,
   }
]
```

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Co-authored-by: isaac hershenson <[email protected]>
Co-authored-by: Isaac Francisco <[email protected]>