Fix another zuul-server reference
Fix another zuul-server reference

Fix another place where zuul-scheduler references the zuul-server
service. This service doesn't exist in v3.

Signed-off-by: Jamie Lennox <1b9801e8e46f6bd96338b24e58c84c4f37762fc2@gmail.com>

BonnyCI/hoist,BonnyCI/hoist,SpamapS/hoist,SpamapS/hoist