Cron Schedule might not trigger with some timezones set in the preferences. #5096
Description
Bug Description
When using the timezone 'America/Chihuahua', cron jobs would not trigger at all.
How to Reproduce
Steps to reproduce the behavior:
- Set the default timezone to 'America/Chihuahua' in the Admin preferences.
- Schedule a cron job to run every minute for _system_cron::sendEmail()
Cause
The 'intl' extension (depending on the version of PHP) may not be up-to-date. This caused a 1 hour difference for the timezone above, so the cron time would never match the calculate 'NOW' time.