Importing issues CSV retried multiple times

In https://gitlab.com/gitlab-org/gitlab-ce/issues/64692, we saw a job in the import_issues_csv attempt multiple times. There are a few things here to investigate:

1. The job keeps starting, but never finished? Is it being killed due to OOM (https://gitlab.com/gitlab-org/sidekiq-reliable-fetch/issues/19)?
2. The CSV is weird, but should work (I have the file in a snippet, but it's private - https://gitlab.com/snippets/1876685 - and I can't create a project snippet for it without getting a 502 😞 ).
3. Do we need to reduce the maximum file size for this job?