[V1][P/D] Release nixl xfer handles

[ptarasiewiczNV]

nixl_wrapper.release_xfer_handle is fixed in the current NIXL release so it can be called to release the transfer handles after they are done so they are not kept in memory.

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[NickLucche]

Thanks!
Without this free the little memory used by the handle is leaking did I get that right?

[NickLucche]

On second thought, this implies nixl>=0.2.0 right?

[ptarasiewiczNV]

Without this free the little memory used by the handle is leaking did I get that right?
Correct

On second thought, this implies nixl>=0.2.0 right?
Yes, I have tested with 0.2.1, but possible that it's been fixed in 0.1.1 as well, I will check and get back to you

[njhill]

Thanks @ptarasiewiczNV. Closing since this was included in #18833.