ci: extend experiment timeout for slurm test

[MikhailKardash]

Ticket

None

Description

Slurm restart fails on main because the underlying trials time out due to image pull. This PR does 2 things:

1. Bypasses top-level config for trial timeout in the affected test to wait for image pulls.
2. Adds the affected test suite to be testable on feature branches.

Test Plan

CI passes, specifically: test-e2e-slurm-restart

Checklist

• [ ] Changes have been manually QA'd
• [ ] New features have been approved by the corresponding PM
• [ ] User-facing API changes have the "User-facing API Change" label
• [ ] Release notes have been added as a separate file under docs/release-notes/ See Release Note for details.
• [ ] Licenses have been included for new code which was copied and/or modified from any external code