Download retried RSpec results first

What does this MR do and why?

We usually retry RSpec failures in a new RSpec process and save test results in a separate JSON file. I think it makes sense to download this file (which is smaller btw) to look for the final failures of a job.

That would avoid confusing assignments of incidents that are based on failures that didn't happen in the retry process (e.g. gitlab-org/quality/engineering-productivity/master-broken-incidents#5078 (closed) / https://gitlab.slack.com/archives/CMMF8TKR9/p1706516722518419?thread_ts=1706251800.500109&cid=CMMF8TKR9).

Expected impact & dry-runs

These are strongly recommended to assist reviewers and reduce the time to merge your change.

See https://gitlab.com/gitlab-org/quality/triage-ops/-/tree/master/doc/scheduled#testing-policies-with-a-dry-run on how to perform dry-runs for new policies.

See https://gitlab.com/gitlab-org/quality/triage-ops/-/blob/master/doc/reactive/best_practices.md#use-the-sandbox-to-test-new-processors on how to make sure a new processor can be tested.

Action items

• If adding environment variables for reactive processors, update config/triage-web.yaml and .gitlab/ci/triage-web.yml
• (If applicable) Add documentation to the handbook pages for Triage Operations =>
• (If applicable) Identify the affected groups and how to communicate to them:
  • /cc @person_or_group =>
  • Relevant Slack channels =>
  • Engineering week-in-review