Fix race condition in concurrent backups

Merged James Fargher requested to merge backup_wrap_concurrency into master

What does this MR do?

Fixes #238847 (closed)

As per https://guides.rubyonrails.org/threading_and_code_execution.html we need to wrap all threaded code that uses rails application code to prevent code loading races.

Screenshots

Does this MR meet the acceptance criteria?

Conformity

Availability and Testing

Security

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  • Label as security and @ mention @gitlab-com/gl-security/appsec
  • The MR includes necessary changes to maintain consistency between UI, API, email, or other methods
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Edited by Kamil Trzciński