Don't fire X509CertNearExpired alert for *.rsc.cdn77.org endpoints

CDN77 seems to fly pretty close to the sun with renewing certificates for our CDN resources. Since we don't have control over this and it also has not yet caused us problems, is there a way to remove this alert for CDN77 endpoints? Our alerts mailing list is already full of alerts we ignore and it would be nice to remove this one too. It looks like this alert is part of the tpa_blackbox group. The other reachability checks are still really useful to us and it would be nice to keep them.

Thanks!