Require tokio-util 0.7.10 for TaskTracker

Ensure dependency resolution cannot retain a tokio-util release that
predates the TaskTracker API used by the runtime.

AI-assisted-by: OpenAI Codex

Author: tankyleo

Cargo.toml

@@ -70,7 +70,7 @@ base64 = { version = "0.22.1", default-features = false, features = ["std"] }
 getrandom = { version = "0.3", default-features = false }
 chrono = { version = "0.4", default-features = false, features = ["clock"] }
 tokio = { version = "1.39", default-features = false, features = [ "rt-multi-thread", "time", "sync", "macros", "net" ] }
-tokio-util = { version = "0.7", default-features = false, features = ["rt"] }
+tokio-util = { version = "0.7.10", default-features = false, features = ["rt"] }
 esplora-client = { version = "0.12", default-features = false, features = ["tokio", "async-https-rustls"] }
 ldk-esplora-client = { package = "esplora-client", version = "0.13", default-features = false, features = ["tokio", "async-https-rustls"] }
 electrum-client = { version = "0.25", default-features = false, features = ["proxy", "use-rustls-ring"] }