Use any index specified by .watches for Watcher (#39541)#39706

AthenaEryma merged 2 commits intoelastic:6.7elastic/elasticsearch:6.7from

AthenaEryma:backport/6.7/watcher/always-obey-aliasesAthenaEryma/elasticsearch:backport/6.7/watcher/always-obey-aliasesCopy head branch name to clipboard