channelinfo does not work on forum channels

[core-bulbbot]

/channelinfo does not work on forum channels

Run /channelinfo on a forum channel, and see that it does not work, relevant error
https://canary.discord.com/channels/818176562901549066/822864327303757874/1012656591759220747

Issue created by mrphilip#1337 (190160914765316096)

[not-lumen]

waiting for discordjs/discord.js#7791