Bug 23384: Remove user arthuredelstein on build-sunet-a.torproject.net

Arthur said he doesn't need access to this machine anymore, so we remove
his user account from the ansible config (the account will be removed
from the machine manually).

tools/ansible/roles/tbb-team/defaults/main.yml

 ---
 tbb_team_members:
-    - arthuredelstein
     - boklm
     - brade
     - gk

tools/ansible/roles/tbb-team/files/arthuredelstein.pub

-ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQDTn6K3kVN90fKK4BFC2I6wU9Ngb0v1U9JG9Ongt8UlTnbT58tLXATj65a7JwLcFHTjfTyDe2YLA5ujec2Az9LVYNezf4lIbykkDMg125En0HVhjanae9JwCWbOH9BhaEcB9ILc/gAeEXedxvZjpdTkcuJRoYem0jzyBXIm1eCb7gSbGJ5ma9JVFysOxFFor3SiOAjTDotgqVtfG3SF0ecRnViO/dfW9sCzwpTABOg0FZTKV/0AzbPoLE9w8OGe3qZU/eyK+Uw4gP/ZmF9veP1Npnvhf3wS4xkyg0zIvhIeOWQyArbir7dr0xTPhoOv3+GrDwKfCVfEvLEAwcL4TZPx arthur@Arthur.local