Update prost-build requirement from 0.8.0 to 0.12.3

Updates the requirements on [prost-build](https://github.com/tokio-rs/prost) to permit the latest version.
- [Release notes](https://github.com/tokio-rs/prost/releases)
- [Commits](tokio-rs/prost@v0.8.0...v0.12.3)

---
updated-dependencies:
- dependency-name: prost-build
  dependency-type: direct:production
...

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

k8s-pb-codegen/Cargo.toml

@@ -8,7 +8,7 @@ publish = false
 [dependencies]
 bytes = "1.0.1"
 prost = "0.8.0"
-prost-build = "0.8.0"
+prost-build = "0.12.3"
 prost-types = "0.8.0"
 serde_json = "1.0.67"
 serde = { version = "1.0.130", features = ["derive"] }