Bump protoVersion from 4.27.2 to 4.28.0

Bumps `protoVersion` from 4.27.2 to 4.28.0.

Updates `com.google.protobuf:protobuf-java` from 4.27.2 to 4.28.0
- [Release notes](https://github.com/protocolbuffers/protobuf/releases)
- [Changelog](https://github.com/protocolbuffers/protobuf/blob/main/protobuf_release.bzl)
- [Commits](https://github.com/protocolbuffers/protobuf/commits)

Updates `com.google.protobuf:protobuf-java-util` from 4.27.2 to 4.28.0

Updates `com.google.protobuf:protoc` from 4.27.2 to 4.28.0
- [Release notes](https://github.com/protocolbuffers/protobuf/releases)
- [Changelog](https://github.com/protocolbuffers/protobuf/blob/main/protobuf_release.bzl)
- [Commits](https://github.com/protocolbuffers/protobuf/commits)

---
updated-dependencies:
- dependency-name: com.google.protobuf:protobuf-java
  dependency-type: direct:production
  update-type: version-update:semver-minor
- dependency-name: com.google.protobuf:protobuf-java-util
  dependency-type: direct:production
  update-type: version-update:semver-minor
- dependency-name: com.google.protobuf:protoc
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

router-protobuf/build.gradle.kts

@@ -6,7 +6,7 @@ repositories {
     mavenCentral()
 }
 
-val protoVersion = "4.27.2"
+val protoVersion = "4.28.0"
 
 dependencies {
     implementation(kotlin("stdlib"))