Bump tokio-util from 0.6.9 to 0.7.0

Bumps [tokio-util](https://github.com/tokio-rs/tokio) from 0.6.9 to 0.7.0.
- [Release notes](https://github.com/tokio-rs/tokio/releases)
- [Commits](https://github.com/tokio-rs/tokio/commits)

---
updated-dependencies:
- dependency-name: tokio-util
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

Author: dependabot[bot]

Cargo.lock

@@ -56,11 +56,11 @@ tracing-subscriber = { version = "0.3", features = ["fmt", "json", "time"] }
 tracing-appender = "0.2"
 tokio = { version = "^1.15", features = ["rt-multi-thread", "time", "sync", "rt", "signal", "test-util"] }
 tokio-stream = { version = "0.1.4", features = ["sync"] }
-tokio-util = { version = "0.6.0", features = ["time"] }
+tokio-util = { version = "0.7.0", features = ["time"] }
 tonic = "0.6"
 lru = "0.7"
 warp = { version = "0.3.2", features = ["tls"] }
-serde_with = { version = "1.11", features = ["macros"] }
+serde_with = { version = "1.12", features = ["macros"] }
 http-zipkin = "0.3.0"
 prometheus = { version = "0.13", optional = true }