Improve error message for Reddit errors

[TimJentzsch]

Some commands, such as /rules and /pirules need to contact the Reddit API.
Unfortunately, this sometimes errors, e.g. a 400 response code for some reason.

The user in this case gets a very generic response:

[2aeae1ac-d993-4f6e-819b-cfd859999f95] Something went wrong, please contact a moderator with the provided ID.

Instead, the user should be notified that the Reddit API seems to have issues and that they should try again in a couple of minutes.

[itsthejoker]

Is it always a 100% guarantee that a 400 error is on reddit's side?

[TimJentzsch]

Probably not, 400 means bad request so that's already the wrong response code lol.

Ideally we'd add a global handler like we have have for Discord errors and such, but for PRAW errors.