Describe the idea
Sidekiq 8 is on it's way, changing how created_at (et.al) are stored. This needs to be supported in sentry-Sidekiq queue instrumentation.

Why do you think it's beneficial to most of the users
To avoid faulty timings in Queues page.

Possible implementation
Look at type of created_at, as it's changing from float to int - Or branch into Sidekiq-version >= 8

See also:
https://github.com/sidekiq/sidekiq/blob/main/Changes.md#head--main

WARNING The created_at, enqueued_at, failed_at and retried_at attributes are now stored as epoch milliseconds, rather than epoch floats. This is meant to avoid precision issues with JSON and JavaScript's 53-bit Floats. Example: "created_at" => 1234567890.123456 -> "created_at" => 1234567890123.