chore: bump futures from 0.3.15 to 0.3.16 (#18914)

* chore: bump futures from 0.3.15 to 0.3.16

Bumps [futures](https://github.com/rust-lang/futures-rs) from 0.3.15 to 0.3.16.
- [Release notes](https://github.com/rust-lang/futures-rs/releases)
- [Changelog](https://github.com/rust-lang/futures-rs/blob/master/CHANGELOG.md)
- [Commits](https://github.com/rust-lang/futures-rs/compare/0.3.15...0.3.16)

---
updated-dependencies:
- dependency-name: futures
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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* [auto-commit] Update all Cargo lock files

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: dependabot-buildkite <you@example.com>

ledger/Cargo.toml

@@ -17,7 +17,7 @@ chrono-humanize = "0.2.1"
 crossbeam-channel = "0.5"
 ed25519-dalek = "1.0.1"
 fs_extra = "1.2.0"
-futures = "0.3.15"
+futures = "0.3.16"
 futures-util = "0.3.16"
 itertools = "0.10.1"
 lazy_static = "1.4.0"