ClassLoading like that no longer valid with spigot 1.13

[Pingger]

https://github.com/RegalOwl/HyperConomy/blob/424200b94fd2fb57364a5f36e927ee040e2d480b/src/main/java/regalowl/hyperconomy/util/LibraryManager.java#L227-L237

After fixing the code in d45783b in #149

Spigot warns (as described in the blog post about 1.13), that the functionality is no longer valid and will be prohibited once released:

WARNING: An illegal reflective access operation has occurred
WARNING: Illegal reflective access by regalowl.hyperconomy.util.LibraryManager (file:/B:/spigotmc_1.13/server/plugins/hyperconomy-0.975.8-SNAPSHOT.jar) to method java.net.URLClassLoader.addURL(java.net.URL)
WARNING: Please consider reporting this to the maintainers of regalowl.hyperconomy.util.LibraryManager
WARNING: Use --illegal-access=warn to enable warnings of further illegal reflective access operations
WARNING: All illegal access operations will be denied in a future release

Additionally using the old (before my commit, so the way it is now) method with Java 8 in spigot 1.13 (after fixing the NBTTools) yields classpath errors, that prevent the server from accessing its classes and then crashing with pseudo random java.lang.ClassDefNotFoundExceptions (depending on when the first library is loaded)
Example Log1: https://pastebin.com/RWKRhyzm
Example Log2: https://pastebin.com/Pndn5TvH

Greetings