Add compatibility with MC 1.20.6

[MusclePr]

I am always indebted to Yamipa.

I am just reporting this because it did not start with 1.20.6.

Starting org.bukkit.craftbukkit.Main
System Info: Java 21 (OpenJDK 64-Bit Server VM 21.0.3+9-LTS) Host: Linux 6.5.13-3-pve (amd64)
Loading libraries, please wait...
WARN StatusConsoleListener The use of package scanning to locate plugins is deprecated and will be removed in a future release
WARN StatusConsoleListener The use of package scanning to locate plugins is deprecated and will be removed in a future release
WARN StatusConsoleListener The use of package scanning to locate plugins is deprecated and will be removed in a future release
WARN StatusConsoleListener The use of package scanning to locate plugins is deprecated and will be removed in a future release
[08:29:14] [ServerMain/INFO]: Environment: Environment[sessionHost=https://sessionserver.mojang.com, servicesHost=https://api.minecraftservices.com, name=PROD]
[08:29:14] [ServerMain/INFO]: Loaded 1175 recipes
[08:29:15] [ServerMain/INFO]: Loaded 1276 advancements
[08:29:15] [Server thread/INFO]: Starting minecraft server version 1.20.6
[08:29:15] [Server thread/INFO]: Loading properties
[08:29:15] [Server thread/INFO]: This server is running Paper version 1.20.6-82-master@0ad09de (2024-05-18T20:25:01Z) (Implementing API version 1.20.6-R0.1-SNAPSHOT)
[08:29:15] [Server thread/INFO]: Server Ping Player Sample Count: 12
[08:29:15] [Server thread/INFO]: Using 4 threads for Netty based IO
[08:29:16] [Server thread/WARN]: [!] The timings profiler has been enabled but has been scheduled for removal from Paper in the future.
    We recommend installing the spark profiler as a replacement: https://spark.lucko.me/
    For more information please visit: https://github.com/PaperMC/Paper/issues/8948
[08:29:16] [Server thread/INFO]: Chunk system is using 1 I/O threads, 4 worker threads, and gen parallelism of 4 threads
[08:29:16] [Server thread/INFO]: Default game type: CREATIVE
[08:29:16] [Server thread/INFO]: Generating keypair
[08:29:16] [Server thread/INFO]: Starting Minecraft server on *:25565
[08:29:16] [Server thread/INFO]: Using epoll channel type
[08:29:16] [Server thread/INFO]: Paper: Using libdeflate (Linux x86_64) compression from Velocity.
[08:29:16] [Server thread/INFO]: Paper: Using OpenSSL 3.0.x (Linux x86_64) cipher from Velocity.
[08:29:16] [Server thread/INFO]: Loading server plugin ProtocolLib v5.2.1-SNAPSHOT-689
[08:29:16] [Server thread/WARN]: Version (MC: 1.20.6) has not yet been tested! Proceed with caution.
[08:29:17] [Server thread/INFO]: Loading server plugin YamipaPlugin v1.3.1
[08:29:17] [Server thread/INFO]: Server permissions file permissions.yml is empty, ignoring it
[08:29:17] [Server thread/INFO]: Enabling ProtocolLib v5.2.1-SNAPSHOT-689
[08:29:17] [Server thread/WARN]: **** SERVER IS RUNNING IN OFFLINE/INSECURE MODE!
[08:29:17] [Server thread/WARN]: The server will make no attempt to authenticate usernames. Beware.
[08:29:17] [Server thread/WARN]: Whilst this makes it possible to use BungeeCord, unless access to your server is properly restricted, it also opens up the ability for hackers to connect with any username they choose.
[08:29:17] [Server thread/WARN]: Please see http://www.spigotmc.org/wiki/firewall-guide/ for further information.
[08:29:17] [Server thread/WARN]: To change this, set "online-mode" to "true" in the server.properties file.
[08:29:17] [Server thread/INFO]: Preparing level "world"
[08:29:17] [Server thread/INFO]: Preparing start region for dimension minecraft:overworld
[08:29:18] [Server thread/INFO]: Time elapsed: 363 ms
[08:29:18] [Server thread/INFO]: Preparing start region for dimension minecraft:the_nether
[08:29:18] [Server thread/INFO]: Time elapsed: 75 ms
[08:29:18] [Server thread/INFO]: Preparing start region for dimension minecraft:the_end
[08:29:18] [Server thread/INFO]: Time elapsed: 60 ms
[08:29:18] [Server thread/INFO]: Enabling YamipaPlugin v1.3.1
[08:29:18] [Server thread/ERROR]: Error occurred while enabling YamipaPlugin v1.3.1 (Is it up to date?)
java.lang.ExceptionInInitializerError: null
        at Yamipa.jar/io.josemmo.bukkit.plugin.commands.ImageCommandBridge.register(ImageCommandBridge.java:29) ~[?:?]
        at Yamipa.jar/io.josemmo.bukkit.plugin.YamipaPlugin.onEnable(YamipaPlugin.java:90) ~[?:?]
        at org.bukkit.plugin.java.JavaPlugin.setEnabled(JavaPlugin.java:287) ~[paper-api-1.20.6-R0.1-SNAPSHOT.jar:?]
        at io.papermc.paper.plugin.manager.PaperPluginInstanceManager.enablePlugin(PaperPluginInstanceManager.java:202) ~[paper-1.20.6.jar:1.20.6-82-0ad09de]
        at io.papermc.paper.plugin.manager.PaperPluginManagerImpl.enablePlugin(PaperPluginManagerImpl.java:109) ~[paper-1.20.6.jar:1.20.6-82-0ad09de]
        at org.bukkit.plugin.SimplePluginManager.enablePlugin(SimplePluginManager.java:519) ~[paper-api-1.20.6-R0.1-SNAPSHOT.jar:?]
        at org.bukkit.craftbukkit.CraftServer.enablePlugin(CraftServer.java:604) ~[paper-1.20.6.jar:1.20.6-82-0ad09de]
        at org.bukkit.craftbukkit.CraftServer.enablePlugins(CraftServer.java:553) ~[paper-1.20.6.jar:1.20.6-82-0ad09de]
        at net.minecraft.server.MinecraftServer.loadWorld0(MinecraftServer.java:678) ~[paper-1.20.6.jar:1.20.6-82-0ad09de]
        at net.minecraft.server.MinecraftServer.loadLevel(MinecraftServer.java:437) ~[paper-1.20.6.jar:1.20.6-82-0ad09de]
        at net.minecraft.server.dedicated.DedicatedServer.initServer(DedicatedServer.java:323) ~[paper-1.20.6.jar:1.20.6-82-0ad09de]
        at net.minecraft.server.MinecraftServer.runServer(MinecraftServer.java:1139) ~[paper-1.20.6.jar:1.20.6-82-0ad09de]
        at net.minecraft.server.MinecraftServer.lambda$spin$0(MinecraftServer.java:323) ~[paper-1.20.6.jar:1.20.6-82-0ad09de]
        at java.base/java.lang.Thread.run(Unknown Source) [?:?]
Caused by: java.lang.RuntimeException: Failed to get internal classes due to incompatible Minecraft server
        at Yamipa.jar/io.josemmo.bukkit.plugin.utils.Internals.<clinit>(Internals.java:52) ~[?:?]
        ... 14 more
Caused by: java.lang.NoSuchFieldException: vanillaCommandDispatcher
        at java.base/java.lang.Class.getDeclaredField(Unknown Source) ~[?:?]
        at io.papermc.reflectionrewriter.runtime.AbstractDefaultRulesReflectionProxy.getDeclaredField(AbstractDefaultRulesReflectionProxy.java:90) ~[reflection-rewriter-runtime-0.0.1.jar:?]
        at io.papermc.paper.pluginremap.reflect.PaperReflectionHolder.getDeclaredField(Unknown Source) ~[paper-1.20.6.jar:1.20.6-82-0ad09de]
        at Yamipa.jar/io.josemmo.bukkit.plugin.utils.Internals.<clinit>(Internals.java:34) ~[?:?]
        ... 14 more
[08:29:18] [Server thread/INFO]: Disabling YamipaPlugin v1.3.1
[08:29:18] [Server thread/INFO]: Starting remote control listener
[08:29:18] [Server thread/INFO]: Thread RCON Listener started
[08:29:18] [Server thread/INFO]: RCON running on 0.0.0.0:25575
[08:29:18] [Server thread/INFO]: Running delayed init tasks
[08:29:18] [Server thread/INFO]: Done (3.314s)! For help, type "help"
[08:29:18] [Server thread/INFO]: Timings Reset