Pass project ID to issue placement worker

What does this MR do?

This MR changes the arguments to the IssuePlacementWorker to take a project_id.

The reasoning here is:

• the issue is representative. We move unpositioned items in the set, and any issue in the project will do
• passing project ID allows for de-duplicating requests. Since we schedule a further repositioning if not all issues were moved, this means we should be OK to discard concurrent requests

This is related to gitlab-com/gl-infra/production#2698 (closed), although not strictly speaking a cause (fewer workers does mean fewer errors though, and this would keep us under the SLA during spikes).

For similar work see: !40746 (merged)

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