Update tokio requirement from =1.38.1 to =1.39.2

Updates the requirements on [tokio](https://github.com/tokio-rs/tokio) to permit the latest version.
- [Release notes](https://github.com/tokio-rs/tokio/releases)
- [Commits](tokio-rs/tokio@tokio-1.38.1...tokio-1.39.2)

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

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

Author: dependabot[bot]

Cargo.toml

@@ -41,7 +41,7 @@ rand = { version = "^0.8", features = ["std", "std_rng"], optional = true }
 # version_sync: to ensure versions in `Cargo.toml` and `README.md` are in sync
 version-sync = "0.9.4"
 rand = { version = "0.8.5", features = ["getrandom"] }
-tokio = { version = "=1.38.1", features = ["full"] }
+tokio = { version = "=1.39.2", features = ["full"] }
 bloomfilter = "^1.0"
 ethabi = "^18.0"