Follow-up from "Remove `project_export_as_ndjson` and `project_import_ndjson` FFs"
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The following discussion from !110729 should be addressed:
- [ ] @georgekoltsov started a [discussion](https://gitlab.com/gitlab-org/gitlab/-/merge_requests/110729#note_1315018058):
> I don't really fully understand why we have a separate spec for import of forked projects, perhaps there was a bug for this use case? I wonder if we should keep a similar spec but for ndjson use case? Can be a follow up. WDYT?
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