chore(deps): bump tokio-util from 0.6.7 to 0.6.8 (#434)

Bumps [tokio-util](https://github.com/tokio-rs/tokio) from 0.6.7 to 0.6.8.
- [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-patch
...

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

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Cargo.lock

@@ -3016,9 +3016,9 @@ dependencies = [
 
 [[package]]
 name = "tokio-util"
-version = "0.6.7"
+version = "0.6.8"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "1caa0b0c8d94a049db56b5acf8cba99dc0623aab1b26d5b5f5e2d945846b3592"
+checksum = "08d3725d3efa29485e87311c5b699de63cde14b00ed4d256b8318aa30ca452cd"
 dependencies = [
  "bytes",
  "futures-core",

ethers-providers/Cargo.toml

@@ -40,7 +40,7 @@ bytes = { version  = "1.1.0", default-features = false, optional = true }
 
 [target.'cfg(not(target_arch = "wasm32"))'.dependencies]
 # tokio
-tokio-util = { version = "0.6.7", default-features = false, features = ["io"], optional = true }
+tokio-util = { version = "0.6.8", default-features = false, features = ["io"], optional = true }
 tokio = { version = "1.5", default-features = false, optional = true }
 tokio-tungstenite = { version = "0.15.0", default-features = false, features = ["connect"], optional = true }