Bump prost from 0.12.4 to 0.12.6 in /rustclient/lib (#219)

Bumps [prost](https://github.com/tokio-rs/prost) from 0.12.4 to 0.12.6.
- [Release notes](https://github.com/tokio-rs/prost/releases)
- [Commits](tokio-rs/prost@v0.12.4...v0.12.6)

---
updated-dependencies:
- dependency-name: prost
  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>

rustclient/lib/Cargo.toml

@@ -10,7 +10,7 @@ license = "MIT"
 
 [dependencies]
 tonic = "0.11.0"
-prost = "0.12.4"
+prost = "0.12.6"
 tokio = { version = "1.37", features = ["macros", "rt-multi-thread"] }
 futures = "0.3.30"
 async-stream = "0.3.5"