GitLab CI: Fix Ruff CI job
It didn't check any files because calling bin/test-utils/is-file-type failed with:
/usr/bin/env: 'python3': No such file or directory
Closes #20266 (closed)
It didn't check any files because calling bin/test-utils/is-file-type failed with:
/usr/bin/env: 'python3': No such file or directory
Closes #20266 (closed)