ctl check: check if two bot use the same cache db

Idea for the intelmqctl check method:

Check if there are two bots which use the same redis cache database, issue a warning if this is the case. Bots should use the databases >= 10.

Can easily lead to false positives, especially with multiple instances of the same bot.

Maybe instead only check that no two different bot modules use the same database, e.g. two completely different experts should not use the same DB, but two deduplicators are allowed to use the same one.