ADD ISRG Root X2

[liuxyon]

The ISRG Root X2 root certificate is already trusted by browsers and operating systems and is already in use.
ssllabs.com still not updated.

https://valid-isrgrootx2.letsencrypt.org/

https://www.ssllabs.com/ssltest/analyze.html?d=valid-isrgrootx2.letsencrypt.org

[Nauman Shah]

Hi @liuxyon

This is already a part of dev.ssllabs.com. Soon the changes will be available on www.ssllabs.com
https://dev.ssllabs.com/ssltest/analyze.html?d=valid-isrgrootx2.letsencrypt.org

Regards,
Nauman Shah