Use single variable for compiler and runtime

pom.xml

@@ -31,7 +31,7 @@
 
   <properties>
     <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
-    <protoc.version>4.28.3</protoc.version>
+    <protobuf.version>4.28.3</protobuf.version>
   </properties>
 
   <build>
@@ -70,7 +70,7 @@
         <artifactId>protobuf-maven-plugin</artifactId>
         <version>0.6.1</version>
         <configuration>
-          <protocArtifact>com.google.protobuf:protoc:${protoc.version}:exe:${os.detected.classifier}</protocArtifact>
+          <protocArtifact>com.google.protobuf:protoc:${protobuf.version}:exe:${os.detected.classifier}</protocArtifact>
         </configuration>
         <executions>
           <execution>
@@ -154,7 +154,7 @@
     <dependency>
       <groupId>com.google.protobuf</groupId>
       <artifactId>protobuf-java</artifactId>
-      <version>4.28.3</version>
+      <version>${protobuf.version}</version>
     </dependency>
   </dependencies>