blacklist two license rest tests when build.snapshot=false (elastic/x-pack-elasticsearch#2559)
blacklist two license rest tests when build.snapshot=false (elastic/x-pack-elasticsearch#2559)

There are two rest tests that rely on hardcoded license
signatures that use the dev public key. These tests fail
when tests are run with build.snapshot=false. This Commit
blacklists these two tests in that scenario

relates elastic/x-pack-elasticsearch#2527.

Original commit: elastic/x-pack-elasticsearch@7581e8d69981a492ce955c07ee4fdff96c154f08

GlenRSmith/elasticsearch,gingerwizard/elasticsearch,scorpionvicky/elasticsearch,robin13/elasticsearch,gfyoung/elasticsearch,uschindler/elasticsearch,gfyoung/elasticsearch,coding0011/elasticsearch,gfyoung/elasticsearch,nknize/elasticsearch,gingerwizard/elasticsearch,HonzaKral/elasticsearch,gingerwizard/elasticsearch,gingerwizard/elasticsearch,nknize/elasticsearch,coding0011/elasticsearch,gingerwizard/elasticsearch,gfyoung/elasticsearch,uschindler/elasticsearch,scorpionvicky/elasticsearch,coding0011/elasticsearch,uschindler/elasticsearch,gingerwizard/elasticsearch,robin13/elasticsearch,nknize/elasticsearch,HonzaKral/elasticsearch,GlenRSmith/elasticsearch,scorpionvicky/elasticsearch,nknize/elasticsearch,nknize/elasticsearch,gfyoung/elasticsearch,GlenRSmith/elasticsearch,GlenRSmith/elasticsearch,robin13/elasticsearch,robin13/elasticsearch,scorpionvicky/elasticsearch,HonzaKral/elasticsearch,HonzaKral/elasticsearch,GlenRSmith/elasticsearch,scorpionvicky/elasticsearch,robin13/elasticsearch,coding0011/elasticsearch,uschindler/elasticsearch,gingerwizard/elasticsearch,coding0011/elasticsearch,uschindler/elasticsearch