Log source IP when logging is enabled

We will only enable logging for non-production environment, so there shouldn't be any privacy concerns by enabling this.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=198744739

java/google/registry/proxy/ProxyServer.java

@@ -203,7 +203,7 @@ public class ProxyServer implements Runnable {
 
   public static void main(String[] args) throws Exception {
     // Use JDK logger for Netty's LoggingHandler,
-    // which is what google.registry.util.FormattingLog uses under the hood.
+    // which is what Flogger uses under the hood.
     InternalLoggerFactory.setDefaultFactory(JdkLoggerFactory.INSTANCE);
 
     // Configure the components, this needs to run first so that the logging format is properly