Rename ProjectServiceWorker to Integrations::ExecuteWorker

What does this MR do and why?

This is part of our rename from "services" to "integrations" in &2504 (closed).

We also rename the Sidekiq queue in a post-deployment migration.

Migration output

$ rake db:migrate:up:main VERSION=20220525141540
main: == 20220525141540 MigrateProjectServiceWorkerQueue: migrating =================
main: == 20220525141540 MigrateProjectServiceWorkerQueue: migrated (0.0028s) ========

$ rake db:migrate:down:main VERSION=20220525141540
main: == 20220525141540 MigrateProjectServiceWorkerQueue: reverting =================
main: == 20220525141540 MigrateProjectServiceWorkerQueue: reverted (0.0019s) ========

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 to #330670 (closed)