Merge branch 'fix/import-export-retry-settings' into 'master'

Limit number of project export retries to 3

I think 3 should be a sufficient number of retries - at the moment we were doing 20+

This will only send a maximum of 3 emails if the project export went wrong. Tested - project import is not affected.

Fixes https://gitlab.com/gitlab-org/gitlab-ce/issues/18966

See merge request !5267

CHANGELOG

@@ -105,6 +105,7 @@ v 8.10.0 (unreleased)
   - Fix issues importing projects from EE to CE
   - Fix creating group with space in group path
   - Create Todos for Issue author when assign or mention himself (Katarzyna Kobierska)
+  - Limit the number of retries on error to 3 for exporting projects
 
 v 8.9.6
   - Fix importing of events under notes for GitLab projects. !5154

app/workers/project_export_worker.rb

 class ProjectExportWorker
   include Sidekiq::Worker
 
-  sidekiq_options queue: :gitlab_shell, retry: true
+  sidekiq_options queue: :gitlab_shell, retry: 3
 
   def perform(current_user_id, project_id)
     current_user = User.find(current_user_id)