Pull issues from a JIRA Project using the REST API

Create a service or job to robustly draw down all issues for a JIRA project using their REST API.

• Use installed jira-ruby gem;
• Order issues by created_at or sequential ID;
• Handle pagination, e.g. 100 issues per page, so that jobs can be run in parallel, and
• Ensure that issues that have been created since the job started are picked up.

Note It's important to use the jira-ruby gem for predictable serialization of issues, so that work to map to GitLab issues can happen in parallel.

Questions to answer

1. Can issues be sorted by created_at or another sequential ID
   • yes, we can sort issues when pulling from jira by created at. Thank should give us a constant order of issues and we can then paginate through those.
2. Should pages be entered as Sidekiq jobs or one job per issue? Or other? (Affects #208917 (closed))
   • I think it should be a combination of 2. If we would have to import 100K or more issues we would want to pull them in batches of say 1K and then have a import worker for each issue.