[PATCH] selftests/landlock: Fix snprintf truncation checks in test files

[Wang Yan]

Hi maintainers and reviewers,

I hope this email finds you well.

I submitted this patch on June 26, 2026, and it has not received any
review comments yet. I understand you are very busy, but I would
greatly appreciate it if you could take a look when you have a moment.

The patch fixes the remaining snprintf truncation checks in
selftests/landlock test files (audit_test.c, net_test.c, ptrace_test.c)
to match the already-merged fix in audit.h. It is a small and
straightforward change.

Please let me know if any adjustments are needed. I'm happy to update
the patch based on your feedback.

Thank you for your time and work!

Best regards,
Wang Yan