🚀 Feature

Add next_observations and dones fields to the RolloutBuffer and the DictRolloutBuffer classes, similar to how it is done in the ReplayBuffer class.

Motivation

Currently, on-policy algorithms don't store the next observations and dones fields in their buffer in the get_rollouts method. This is because these fields are not required by any of the algorithms in stable-baselines3. However, these fields are required to be stored in the buffer to implement the original variant of the AIRL algorithm in imitation.

Pitch

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Alternatives

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Additional context

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Checklist

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