Resolve "Credentails used for repository import are visible inside the Sidekiq logs (Background Jobs)"

What does this MR do?

Ensures that username/password information isn't leaked from a URL in the importer when erroring.

Are there points in the code the reviewer needs to double check?

Why was this MR needed?

Sensitive information was leaking into errors / sidekiq.

Screenshots (if relevant)

Does this MR meet the acceptance criteria?

• Changelog entry added, if necessary
• Documentation created/updated
• API support added
• Tests added for this feature/bug
• Conform to the code review guidelines
  • Has been reviewed by a UX Designer
  • Has been reviewed by a Frontend maintainer
  • Has been reviewed by a Backend maintainer
  • Has been reviewed by a Database specialist
• Conforms to the merge request performance guidelines
• Conforms to the style guides
• Conform to the database guides
• If you have multiple commits, please combine them into a few logically organized commits by squashing them
• Internationalization required/considered
• End-to-end tests pass (package-and-qa manual pipeline job)

What are the relevant issue numbers?

Closes #49272 (closed)