Use sidekiq job to store telesign score for users

What does this MR do and why?

A worker was created as part of https://gitlab.com/gitlab-org/modelops/anti-abuse/team-tasks/-/issues/503 to address latency in the registrations controller. This MR refactors the send_verification_code_service to use the Abuse::TrustScoreWorker to store the user's telesign score.

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