try to enforce only netty 4.1 in series/0.5

Author: hamnis

.scala-steward.conf

@@ -2,9 +2,10 @@ updates.pin = [
   { groupId = "org.slf4j", artifactId = "slf4j-api", version = "1." },
   { groupId = "ch.qos.logback", artifactId = "logback-classic", version = "1.2." }
   { groupId = "com.typesafe.netty", artifactId = "netty-reactive-streams-http", version = "2." }
+  { groupId = "io.netty", version = "4.1." }
 ]
 
 updates.ignore = [
   { groupId = "com.playframework.netty" }
   { groupId = "org.eclipse.jetty", artifactId = "jetty-client" }
-]
+]