pfpki: notBefore attribute is not visible in webadmin or in DB

[nqb]

Describe the bug
When a certificate is generated through pfpki, you can't see notBefore attribute in web admin or DB.

The only way to get that value is to export base64 certificate and to run an openssl command to extract it.

To Reproduce
Steps to reproduce the behavior:

1. Generate a certificate through pfpki
2. Check notBefore attribute in web admin or in DB

=> You will not find it.

There is a date attribute in DB but it doesn't contain notBefore date

Expected behavior
notBefore date is visible through web admin