0.7.2: ParallelEnv fix

We are releasing TorchRL 0.7.2, a minor update that addresses several important bug fixes to improve the stability and reliability of our library.

This release is particularly crucial as it resolves a critical issue (#2840) where, under certain conditions, the device setting of the parallel environment would prevent the tensors in the buffers from being properly cloned. This resulted in rollouts returning the same tensor instances across steps, potentially leading to incorrect behavior and results.

Due to the severity of this bug, we strongly recommend that all users upgrade to TorchRL 0.7.2 to ensure the accuracy and reliability of their experiments.

The full list of changes can be found below:

• [Doc] Fix formatting errors by @vmoens (#2786)
• [BugFix] correct dim for resolving dtype in _split_and_pad_sequence by @KubaMichalczyk and vmoens (#2801)
• [BugFix] Fix collector with no buffers and devices by @vmoens (#2809)
• [BE] Fix some typos by antoinebrl and @vmoens (#2811)
• [Doc] Add docstring for MCTSForest.extend by @kurtamohler and @vmoens (#2795)
• [CI] Fix libs workflows by @vmoens (#2800)
• [BugFix] Fix env.full_done_specs by @vmoens (#2815)
• [BugFix] Fix batch_locked check in check_env_specs + error message ca… by @vmoens (#2817)
• [BugFix] GAE warning when gamma/lmbda are tensors by louisfaury and @vmoens (#2838)
• [BugFix] Tree make node fix by rolo and @vmoens (#2839)
• [BugFix] Fix PEnv device copies by @vmoens (#2840)

Full Changelog: v0.7.1...v0.7.2