Fix Sidekiq warning

What does this MR do and why?

Sidekiq 7.0 will raise error because parameters are not valid json. Now it's just a warning. This MR makes parameters valid.

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• I have evaluated the MR acceptance checklist for this MR.

Related customers-gitlab-com#4381