Netty: do not use deprecated constants
MODIFY
dd-java-agent/instrumentation/netty-4.1/src/main/java/datadog/trace/instrumentation/netty41/client/NettyHttpClientDecorator.java
dd-java-agent/instrumentation/netty-4.1/src/main/java/datadog/trace/instrumentation/netty41/client/NettyHttpClientDecorator.java
package datadog.trace.instrumentation.netty41.client;
-import static io.netty.handler.codec.http.HttpHeaders.Names.HOST;
+import static io.netty.handler.codec.http.HttpHeaderNames.HOST;
import datadog.trace.agent.decorator.HttpClientDecorator;
import io.netty.handler.codec.http.HttpRequest;

MODIFY
dd-java-agent/instrumentation/netty-4.1/src/main/java/datadog/trace/instrumentation/netty41/server/NettyHttpServerDecorator.java
dd-java-agent/instrumentation/netty-4.1/src/main/java/datadog/trace/instrumentation/netty41/server/NettyHttpServerDecorator.java
package datadog.trace.instrumentation.netty41.server;
-import static io.netty.handler.codec.http.HttpHeaders.Names.HOST;
+import static io.netty.handler.codec.http.HttpHeaderNames.HOST;
import datadog.trace.agent.decorator.HttpServerDecorator;
import io.netty.handler.codec.http.HttpRequest;

Netty: do not use deprecated constants