remove eager pet service account creation

[tlangs]

Ticket:

If Sam creates a Singleton Service Account for the user on user creation, then we don't need to wait for project-specific stuff to happen.

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PR checklist

• Include the JIRA issue number in the PR description and title
• Make sure Swagger is updated if API changes
  • ...and Orchestration's Swagger too!
• If you changed anything in model/, then you should publish a new official rawls-model and update rawls-model in Orchestration's dependencies.
• Get two thumbsworth of PR review
• Verify all tests go green, including CI tests
• Squash commits and merge to develop (branches are automatically deleted after merging)
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