GitHub Actions vs GitLab CI for running test suites — practical comparison?

We're moving off Jenkins and evaluating GitHub Actions vs GitLab CI (we're already on GitLab for source control). For test automation specifically, I care about: - Matrix builds (running same tests against multiple Node/Python versions) - Test parallelisation and sharding - Artifact management (test reports, Playwright traces) - Cost at ~500 test pipeline runs/day - caching reliability for node_modules / pip packages Has anyone used both? The obvious answer is "use GitLab CI since you're already on GitLab" but I want to know if GitHub Actions is meaningfully better for test-heavy workflows.