cargo: bump futures from 0.3.26 to 0.3.28

Bumps [futures](https://github.com/rust-lang/futures-rs) from 0.3.26 to 0.3.28.
- [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/0.3.26...0.3.28)

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

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

deltachat-jsonrpc/Cargo.toml

@@ -19,7 +19,7 @@ serde = { version = "1.0", features = ["derive"] }
 tempfile = "3.3.0"
 log = "0.4"
 async-channel = { version = "1.8.0" }
-futures = { version = "0.3.26" }
+futures = { version = "0.3.28" }
 serde_json = "1.0.91"
 yerpc = { version = "0.4.3", features = ["anyhow_expose"] }
 typescript-type-def = { version = "0.5.5", features = ["json_value"] }