Another blind spot of command sync algorithm

[EQUENOS]

Summary

Unloading app commands with guild_ids which were not specified anywhere else doesn't delete those commands.

Reproduction Steps

• Register an app command X with exclusive guild_ids (by exclusive I mean that those guild_ids are not associated with other commands; by registering I mean adding a command and applying the sync algo)
• Remove the app command X and resync

Minimal Reproducible Code

import disnake
from disnake.ext import commands


class Misc(commands.Cog):
    @commands.slash_command(guild_ids=[859404768992165920])
    async def example(self, inter: disnake.AppCmdInter) -> None:
        ...


bot = commands.InteractionBot(command_sync_flags=commands.CommandSyncFlags.all())
bot.add_cog(Misc())


@bot.event
async def on_ready():
    bot.remove_cog("Misc")
    print("Bot is ready. You can check the list of commands")


bot.run("BOT_TOKEN")

Expected Results

Command X should be gone

Actual Results

The command stays in the list of commands

Intents

disnake.Intents.default()

System Information

- Python v3.8.6-final
- disnake v2.9.0
    - disnake importlib.metadata: v2.4.0  
- aiohttp v3.8.1
- system info: Windows 10 10.0.19041 AMD64

Checklist

• [X] I have searched the open issues for duplicates.
• [X] I have shown the entire traceback, if possible.
• [X] I have removed my token from display, if visible.

Additional Context

Probably the best solution is to compare ConnectionState._guild_application_commands to the list of invokable slash commands and remove any commands that are included in the first dict but are missing in the second.