Add `MixtureOfAgentsLLM`

[gabrielmbmb]

Description

This PR adds the MixtureOfAgents llm, an special LLM that allows combining an aggregator_llm and a list of proporsers_llms as described in this paper: https://arxiv.org/abs/2406.04692. Although LLMs in distilabel are not in charge of tweaking the input, this special LLM does as it requires to inject the Mixture-of-Agents system prompt in the system prompt of the task allowing passing the references of the proposers_llms.

⚠️ This system prompt injection should work fine with every task, although it hasn't been tested with all the tasks, only with the TextGenerationtask.

In addition and motivated by the addition of the MixtureOfAgentsLLM, this PR adds/updates the following:

• The RuntimeParametersMixin has been updated to automatically handle attributes with type List[RuntimeParametersMixin]. The way to set the runtime parameters for the list of mixins is via a dict in which each key references the position of the mixin in the list to which the runtime parameters wants to be set.
• The CLI has been updated to be able to render List[RuntimeParametersMixin] attributes.
• Custom from_dict method of the Step has been removed as parent method is able to deserialise _Serializable attributes recursively.
• Remove duplicate generate method implementation of AsyncLLMs adding a new _num_generations_param_supported flag that executes the right method to handle the num_generations parameter.

[codspeed-hq[bot]]

CodSpeed Performance Report

Merging #735 will not alter performance

_{Comparing mixture-of-agents (d74e91c) with develop (9d6a152)}

Summary

✅ 1 untouched benchmarks