Usually maintenance mode is disabled. If the call throws, which we see a
lot of when a unleash instance is in terminating state, we should return
a default value.
By having it throw inside of the memoizee function, the response is not
cached, and it will trigger new calls until it return a cachable result.
## About the changes
Every schedule job will now check if maintenance is enabled. This ends
up querying the settings table in the db at least once per second per
running unleash instance. This small fix caches this query for 60
seconds to reduce the load somewhat.
We should reconsider this solution for the long term, but this will be a
great improvement on the short term.
**Logs after this fix running locally.**
We can observe that we resolve settings from the DB once per minute.
Also we should consider giving a warning in section where you enable
maintenance mode that it can take up to a minute to propagate.
### What
Adds `createdByUserId` to all events exposed by unleash. In addition
this PR updates all tests and usages of the methods in this codebase to
include the required number.
