FQDN remapping

[SlimeDog]

Description Sometimes FQDNs with identical stack traces are remapped to a previous FQDN.

Reproduction steps The clearest example is provided by Plan 5.4-b1412, which recently incorporated slimjar to reduce the plugin size. That requires callouts to download dependencies. Many of them are incorrectly remapped to dl.google.com. See the example below.

Expected behavior Only numeric IP addresses should be remapped to FQDNs. FQDNs should not be remapped, even if the stack traces are identical.

Screenshots Here is an example:

Intercepted connection to dl.google.com by plugin Plan
Intercepted connection to hub.spigotmc.org (dl.google.com) by plugin Plan
Intercepted connection to oss.sonatype.org (dl.google.com) by plugin Plan
Intercepted connection to papermc.io by plugin Plan
Intercepted connection to papermc.io (dl.google.com) by plugin Plan
Intercepted connection to repo.md-5.net (dl.google.com) by plugin Plan
Intercepted connection to repo.playeranalytics.net (dl.google.com) by plugin Plan
Intercepted connection to repo.spongepowered.org (dl.google.com) by plugin Plan
Intercepted connection to repo.velocitypowered.com (dl.google.com) by plugin Plan
Intercepted connection to repo.vshnv.tech by plugin Plan
Intercepted connection to repo.vshnv.tech (dl.google.com) by plugin Plan

Server Environment

• OS [Linux, MacOS, Windows] version: Linux
• Java version [java -version] 16.0.2
• Server version [/version]: Spigot 1.17.1-3226
• NetworkInterceptor version [/version NetworkInterceptor]: 3.1.3

[SlimeDog]

This issue results in confusing remapping, but is otherwise uneventful.