sidekiq-ent periodic tasks support

[Cron monitoring](https://docs.sentry.io/platforms/ruby/crons/) has built-in support for sidekiq-cron and sidekiq-scheduler. It would be great if the built-in cron feature of Sidekiq was supported as well. It is limited to [sidekiq-ent](https://sidekiq.org/products/enterprise.html) (the paid version), but I imagine it's still popular enough to consider being included.

In our `sidekiq.rb` we have:

```
Sidekiq.configure_server do |config|
config.periodic do |mgr|
mgr.register("* * * * *", "TestJob") # every minute
end
end
```

It would be awesome if our `sentry.rb` could have:

```
Sentry.init do |config|
config.enabled_patches += [:sidekiq_ent_cron]
end
```

That way we don't have to manually implement check-ins.