Test: use trial license for qa/rolling-upgrade
Test: use trial license for qa/rolling-upgrade

This updates the rolling-upgrade cluster tests to use a trial license so
that security and watcher functionality can be tested. This is needed
as a result of changing the default license type to basic.

Relates elastic/x-pack-elasticsearch#3878
Relates elastic/x-pack-elasticsearch@f899d48

Original commit: elastic/x-pack-elasticsearch@b1cdd526004cf77cd17bc31be1365275515d05a6

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