fix(ci): replace inaccessible MinIO image

[youngsofun]

Summary

• replace the inaccessible quay.io/minio/minio image used by integration tests
• pin the anonymous Chainguard MinIO image by OCI digest
• run the container as root so it can write to the existing ./data bind mount

Context

The daily integration workflow fails before running tests because Quay rejects anonymous pulls with unauthorized: access to the requested resource is not authorized.

Failed job: https://github.com/databendlabs/bendsql/actions/runs/36210613793/job/108316165490

Verification

• docker compose -f tests/docker-compose.yaml config --quiet
• git diff --check
• pulled and started the pinned image with Docker Compose
• curl -fsS http://127.0.0.1:9000/minio/health/live

[chatgpt-codex-connector]

Codex usage limits have been reached for code reviews. Please check with the admins of this repo to increase the limits by adding credits.