Reboot required integration doesn't immediately trigger with critical_days = 0 or warning_days = 0

[ftab]

integrations-extras/reboot_required/datadog_checks/reboot_required/reboot_required.py

Line 43 in 0ce0b22

if deltatime.days > critical_days:

I think the > should be a >=, or maybe a special case should be made for 0 such that it immediately triggers. I'd like to know as soon as possible after an unattended-upgrade occurs that installed something that requires a reboot.