increase file descriptors limits for tests

[grusev]

Reference Issues/PRs

What does this implement or fix?

This is needed for real S3 and GCP tests as file descriptors required are more than initial limit of 100k

Link to S3 run (manual): https://github.com/man-group/ArcticDB/actions/runs/14643182856

Any other comments?

Checklist

Checklist for code changes...

• [ ] Have you updated the relevant docstrings, documentation and copyright notice?
• [ ] Is this contribution tested against all ArcticDB's features?
• [ ] Do all exceptions introduced raise appropriate error messages?
• [ ] Are API changes highlighted in the PR description?
• [ ] Is the PR labelled as enhancement or bug so it appears in autogenerated release notes?