Email certificate expiry reminders

[teon]

• Reminder for cert about to expire for external and internal Defguard URLs (Edge and Core)
• For user own certificates only
• Let's encrypt and custom CA-based will auto-renew
• Send multiple reminders: If validity is < 14 < 7 < 3 < 1
• If expired send expired email

[Va1ter]

@teon how about something like that?

[teon]

@Va1ter yap. IS it in Figma? @moubctez please add this template as well.

[kchudy]

If validity is < 14 < 7 < 3 < 1 days send email to admin.
If expired send expired email