copy untyped payload buffer on read/write

closes #13

(cherry picked from commit 3e1f7e3)

src/main/java/lol/bai/badpackets/impl/payload/UntypedPayload.java

@@ -21,12 +21,17 @@ public static FriendlyByteBuf.Reader<UntypedPayload> reader(ResourceLocation cha
 
     @Override
     public void write(@NotNull FriendlyByteBuf buf) {
-        buf.writeBytes(buffer);
+        buf.writeBytes(buffer.copy());
     }
 
     @Override
     public @NotNull ResourceLocation id() {
         return channelId;
     }
 
+    @Override
+    public FriendlyByteBuf buffer() {
+        return new FriendlyByteBuf(buffer.copy());
+    }
+
 }