The `DST Root CA X3` certificate was missing from cacerts.txt in the old
version. This resulted in failure to connect to Let's Encrypt hosts.
e.g., https://review.coreboot.org

BUG=none
TEST=Made sure my_activity.py continues to function and it can also
connect to review.coreboot.org
Signed-off-by: Raul E Rangel <rrangel@chromium.org>
Change-Id: I519916b58a59b8f13c227218e93c392a63a24800
Reviewed-on: https://chromium-review.googlesource.com/1173064Reviewed-by: Robbie Iannucci <iannucci@chromium.org>
Commit-Queue: Robbie Iannucci <iannucci@chromium.org>