RUSTSEC-2025-0012: `backoff` is unmainted.

[github-actions]

backoff is unmainted.

Details
Status	unmaintained
Package	backoff
Version	0.4.0
URL	ihrwein/backoff#66
Date	2025-03-04

The backoff crate is no longer actively maintained. For exponential backoffs/retrying, you can use the backon crate.

See advisory page for additional details.