Add dependency management for Netty BOM

Author: Trollhunters501

pom.xml

@@ -52,13 +52,15 @@
     </repositories>
 
     <dependencyManagement>
+         <dependencies>
              <dependency>
                 <groupId>io.netty</groupId>
                 <artifactId>netty-bom</artifactId>
                 <version>4.2.12.Final</version>
                 <type>pom</type>
                 <scope>import</scope>
             </dependency>
+         </dependencies>
     </dependencyManagement>
 
     <dependencies>