Backport of ci: split frontend ember jobs into release/1.13.x#16974

hc-github-team-consul-core merged 2 commits intorelease/1.13.xhashicorp/consul:release/1.13.xfrom

backport/loshz/frontend-test-splitting/normally-careful-reptilehashicorp/consul:backport/loshz/frontend-test-splitting/normally-careful-reptileCopy head branch name to clipboard