Run 'crontab -l {user}' command from {user}'s id

Running 'crontab -l {user}' on Solaris from root without auditing context attached (default behavior) fails with error message: 'The audit context for your shell has not been set.' 

Switching to {user} id for this command bypasses this auditing checks.

Without 'crontab -l' working cron.present state will wipe out all existing entries, if they are managed outside of salt.