Update subxt requirement from 0.33 to 0.34

Updates the requirements on [subxt](https://github.com/paritytech/subxt) to permit the latest version.
- [Release notes](https://github.com/paritytech/subxt/releases)
- [Changelog](https://github.com/paritytech/subxt/blob/master/CHANGELOG.md)
- [Commits](paritytech/subxt@v0.33.0...v0.34.0)

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

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

Cargo.toml

@@ -14,7 +14,7 @@ include = ["src/**/*", "LICENSE", "README.md"]
 [dependencies]
 codec = { package = "parity-scale-codec", version = "3"  }
 futures = "0.3"
-subxt = { version = "0.33", features = ["substrate-compat"] }
+subxt = { version = "0.34", features = ["substrate-compat"] }
 
 [dev-dependencies]
 clap = { version = "4", features = ["derive"] }