Bump io.netty:netty-all in /libraries-server

Bumps [io.netty:netty-all](https://github.com/netty/netty) from 4.1.20.Final to 4.1.42.Final.
- [Commits](netty/netty@netty-4.1.20.Final...netty-4.1.42.Final)

---
updated-dependencies:
- dependency-name: io.netty:netty-all
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

libraries-server/pom.xml

@@ -92,7 +92,7 @@
     <properties>
         <httpclient.version>4.5.3</httpclient.version>
         <jetty.version>9.4.27.v20200227</jetty.version>
-        <netty.version>4.1.20.Final</netty.version>
+        <netty.version>4.1.42.Final</netty.version>
         <tomcat.version>8.5.24</tomcat.version>
         <smack.version>4.3.1</smack.version>
         <eclipse.paho.client.mqttv3.version>1.2.0</eclipse.paho.client.mqttv3.version>