Throttle ProjectUpdateRepositoryStorageWorker Jobs

⚠️ ⚠️ ⚠️ Do not merge until given the go ahead - Merge in accordance with the rollout plan in gitlab-com/gl-infra/scalability#436 (closed)

What does this MR do?

This change updates the urgency attribute for ProjectUpdateRepositoryStorageWorker jobs.

It updates it from urgency=low to urgency=throttled.

This means that the jobs will not have a queuing SLO, and we will not alert on long queues of ProjectUpdateRepositoryStorageWorker jobs.

This strategy is discussed in greater detail in gitlab-com/gl-infra/scalability#436 (closed)

Screenshots

Does this MR meet the acceptance criteria?

Conformity

• Changelog entry
• Documentation (if required)
• Code review guidelines
• Merge request performance guidelines
• Style guides
• Database guides
• Separation of EE specific content

Availability and Testing

• Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.
• Tested in all supported browsers
• Informed Infrastructure department of a default or new setting change, if applicable per definition of done

Security

If this MR contains changes to processing or storing of credentials or tokens, authorization and authentication methods and other items described in the security review guidelines:

• 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
• Security reports checked/validated by a reviewer from the AppSec team