fix AbstractProtocol byte stream interference

[Cirsius]

fixes bug with AbstractProtocol inheriting registerConfigurationChangeHandlers() which messed with the byte stream. this might also fix this issue

[florianreuth]

This seems very wrong, they need to be registered in order to have the correct states set for the handlers above. What error does this fix?

[octylphenol]

This seems very wrong, they need to be registered in order to have the correct states set for the handlers above. What error does this fix?

I have absolutely no idea how this works but it does seem to fix #468

[Cirsius]

This seems very wrong, they need to be registered in order to have the correct states set for the handlers above. What error does this fix?

"Cirsius lost connection: Internal Exception: io.netty.handler.codec.DecoderException: java.io.IOException: Packet play/serverbound/minecraft:configuration_acknowledged (class_8591) was larger than I expected, found 9 bytes extra whilst reading packet serverbound/minecraft:configuration_acknowledged" was the error i was getting and this stopped it from happening. ill look into seeing if theres a more proper fix