x509roots/fallback: update bundle

This is an automated CL which updates the NSS root bundle.

Change-Id: Ic5267bf9d66b676e1cfc5fc2ae153afb8f33b29c
Reviewed-on: https://go-review.googlesource.com/c/crypto/+/631635
Auto-Submit: Gopher Robot <[email protected]>
Reviewed-by: Dmitri Shuralyov <[email protected]>
Reviewed-by: Roland Shoemaker <[email protected]>
LUCI-TryBot-Result: Go LUCI <[email protected]>

Author: gopherbot