Increase timeouts for fetching test timing data

What does this MR do?

Follow-up to !2 (merged)

• Increases the ResponseHeaderTimeout (used when retrieving test timing data) from 10s to 30s.
• Adds an overall 120s request Timeout so a slow or stalled response body can't hang the request indefinitely.
• Adds a .gitignore file and excludes JetBrains project files from versioning.

Why was this MR needed?

The API call made to retrieve the test_report (used to inform distribution of tests across nodes) is likely to be slow for the GitLab Runner pipelines since it generates a ~6.3 MB report (example) on demand if it's not already cached, and the result is only cached for two minutes.

A more generous timeout provides a little extra grace for the report generation to complete. It's worth retrieving this report if possible, as it enables more accurate workload distribution across nodes.