Reduce wait timings for Sidekiq jobs

What does this MR do?

This reduces the time spent waiting for Sidekiq jobs to complete in various places.

Why was this MR needed?

Creating a project can time out if it takes more than 60 seconds for an authorized projects job to complete, producing an HTTP 500 in the process. Further, AuthorizedProjectsWorker jobs usually seem to take around 10 seconds with only very little time spent doing actual work. Reducing the wait interval should hopefully reduce the time spent in these jobs.

Does this MR meet the acceptance criteria?

• Changelog entry added, if necessary
• Conform by the merge request performance guides
• Conform by the style guides
• Squashed related commits together

cc @dblessing since you ran into users experiencing the mentioned problems.