Bump futures-executor from 0.3.15 to 0.3.16

Bumps [futures-executor](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-executor
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>

Cargo.lock

@@ -244,9 +244,9 @@ checksum = "af51b1b4a7fdff033703db39de8802c673eb91855f2e0d47dcf3bf2c0ef01f99"
 
 [[package]]
 name = "futures-executor"
-version = "0.3.15"
+version = "0.3.16"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "badaa6a909fac9e7236d0620a2f57f7664640c56575b71a7552fbd68deafab79"
+checksum = "4d0d535a57b87e1ae31437b892713aee90cd2d7b0ee48727cd11fc72ef54761c"
 dependencies = [
  "futures-core",
  "futures-task",