Project can fail to be deleted if a delete is requested whilst BOM processing is occurring

### Current Behavior

If a delete is requested whilst BOM processing is occurring, sometimes you hit this error:

```
ERROR: update or delete on table "PROJECT" violates foreign key constraint "COMPONENT_FK2" on table "COMPONENT" Detail: Key (ID)=(17) is still referenced from table "COMPONENT".
```

The only other reference to this I've seen is in [#2414](https://github.com/DependencyTrack/dependency-track/issues/2414#issuecomment-1412204031).

This isn't a big deal for us, I'm mostly reporting it to help future people searching for the same error understand what's happening.

### Steps to Reproduce

1. Create a project and start importing a BOM
2. Delete the project before BOM processing is finished.

### Expected Behavior

Either:
- the delete request fails, saying that BOM processing is still occurring; or
- the delete request succeeds, and the project is deleted.

### Dependency-Track Version

4.8.2

### Dependency-Track Distribution

Container Image

### Database Server

PostgreSQL

### Database Server Version

15

### Browser

N/A

### Checklist

- [X] I have read and understand the [contributing guidelines](https://github.com/DependencyTrack/dependency-track/blob/master/CONTRIBUTING.md#filing-issues)
- [X] I have checked the [existing issues](https://github.com/DependencyTrack/dependency-track/issues) for whether this defect was already reported