Update tower requirement from 0.4.13 to 0.5.1

Updates the requirements on [tower](https://github.com/tower-rs/tower) to permit the latest version.
- [Release notes](https://github.com/tower-rs/tower/releases)
- [Commits](tower-rs/tower@tower-0.4.13...tower-0.5.1)

---
updated-dependencies:
- dependency-name: tower
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>

Cargo.toml

@@ -52,7 +52,7 @@ serde_path_to_error = "0.1.4"
 serde_urlencoded = "0.7.1"
 snafu = "0.8"
 tokio = { version = "1.17.0", default-features = false, features = ["time"], optional = true }
-tower = { version = "0.4.13", default-features = false, features = ["util", "buffer"] }
+tower = { version = "0.5.1", default-features = false, features = ["util", "buffer"] }
 tower-http = { version = "0.5.1", features = ["map-response-body", "trace"] }
 tracing = { version = "0.1.37", features = ["log"], optional = true }
 url = { version = "2.2.2", features = ["serde"] }