Bump asynchronous-codec from 0.5.0 to 0.6.0

Bumps [asynchronous-codec](https://github.com/mxinden/asynchronous-codec) from 0.5.0 to 0.6.0.
- [Release notes](https://github.com/mxinden/asynchronous-codec/releases)
- [Changelog](https://github.com/mxinden/asynchronous-codec/blob/master/CHANGELOG.md)
- [Commits](mxinden/asynchronous-codec@v0.5.0...v0.6.0)

---
updated-dependencies:
- dependency-name: asynchronous-codec
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

client/network/Cargo.toml

@@ -30,7 +30,7 @@ fnv = "1.0.6"
 fork-tree = { version = "3.0.0", path = "../../utils/fork-tree" }
 futures = "0.3.9"
 futures-timer = "3.0.2"
-asynchronous-codec = "0.5"
+asynchronous-codec = "0.6"
 hex = "0.4.0"
 ip_network = "0.4.1"
 linked-hash-map = "0.5.4"