Add groq completion example

[sklinkert]

Add usage example for groq

groq offers the same API like OpenAPI

https://github.com/tmc/langchaingo/issues/797

PR Checklist

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[sklinkert]

@devalexandre thanks for approving it :)

@tmc can you merge it?

[ImPedro29]

Using GenerateContent method this implementation doesn't work completely. The request model of completions is different to openai defaults. Mine json request:

{
   "model":"llama3-70b-8192",
   "messages":[
      {
         "role":"system",
         "content":[
            {
               "text":"some text...",
               "type":"text"
            },
            {
               "text":"some text...",
               "type":"text"
            }
         ]
      },
      {
         "role":"user",
         "content":[
            {
               "text":"hi",
               "type":"text"
            }
         ]
      }
   ],
   "temperature":0,
   "max_tokens":300
}

Response:

API returned unexpected status code: 400: 'messages.0' : for 'role:system' the following must be satisfied[('messages.0.content' : value must be a string)]

[sklinkert]

@ImPedro29 Have you tried it with the latest version of langchaingo? I had the same error but it worked for me after upgrading it.

[ImPedro29]

I updated and after some corrections to my embed engine, the same errors are appearing: Using version v0.1.9

Error local: https://github.com/tmc/langchaingo/blob/3bb95e19f191fe570a857ff9d65768d68a499cf6/llms/openai/internal/openaiclient/chat.go#L338

POST https://api.groq.com/openai/v1/chat/completions Body in my message above

It looks like groq doesn't support the same models that openai gpt supports... Maybe in a future groq update it could be

Edit: I just tested GenerateContent method