Update plugin protobuf to v0.9.4 (#3929)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

gradle/libs.versions.toml

@@ -23,7 +23,7 @@ kotlin-jvm = { id = "org.jetbrains.kotlin.jvm", version.ref = "kotlin" }
 dokka = { id = "org.jetbrains.dokka", version = "1.8.20" }
 errorprone = { id = "net.ltgt.errorprone", version = "3.1.0" }
 mavenPublish = { id = "com.vanniktech.maven.publish", version = "0.18.0" }
-protobuf = { id = "com.google.protobuf", version = "0.9.3" }
+protobuf = { id = "com.google.protobuf", version = "0.9.4" }
 animalsniffer = { id = "ru.vyarus.animalsniffer", version = "1.7.1" }
 googleJavaFormat = { id = "com.github.sherter.google-java-format", version = "0.9" }