Deleted logging channels do not disappear from the logs list

[Spudds]

Describe the bug
If you delete a logging channel without removing it's logging types first, it still appears when you run !cfg logging. The deleted channel will still show even after removing it's logging types by using the channel ID.

Steps To Reproduce

1. Create a channel and add it to logging
2. Delete the channel (don't remove it's logging types)
3. Run !cfg logging
4. Try to remove it by copying the channel ID and running !cfg logging remove <logging types>
5. The channel will still show on the list, just without anything under Things which will be logged in this channel

Expected behavior
The channel should be gone from the list completely after deletion and after removing it's logging types by using the channel ID.