Sidekiq: Remove Sidekiq polling dependency on front end submission.

[scottsdevelopment]

• https://github.com/department-of-veterans-affairs/va.gov-team-sensitive/blob/master/teams/benefits/architectural-decision-records/sidekiq-guidance.md

Per Sidekiq guidance, we should take extra caution and steps when dealing with dependencies with the front end. Such we have come to the conclusion that the best course of action would be to decouple the front end and the Sidekiq job completely. We had initially adopted a common pattern from the rest of the vets-website project that included this asynchronous polling of the job status, however the user confirmation page makes no use of the actual returned data and removing this polling would allow for an improvement to the confirmation page responsiveness and reduce overhead.

• Remove polling functionality after submission and assert that a completed submission is enough to complete the confirmation.
• Allow the backend api to handle the job, these do not need to be presented to the user at all.

[mjknight50]

After discussing this with @wayne-weibel and @scottsdevelopment , I think it is a good idea.

[aplatt-coforma]

Hey team! Please add your planning poker estimate with Zenhub @danlim715 @mjknight50 @scottsdevelopment @TaiWilkin @ToddWebDev @wayne-weibel