Disable eavesdrop direct publishing job

eavesdrop.openstack.org is now a CNAME to meetings.opendev.org, and
the meeting information is published by the irc-meetings repository
jobs directly via AFS.  There is no need for the zuul-user login any
more.

Change-Id: I88d3cb5c5e33da7efb56b4f7ca4956c9adf82ee0
Depends-On: https://review.opendev.org/c/openstack/project-config/+/794091

playbooks/service-eavesdrop.yaml

@@ -9,7 +9,6 @@
   strategy: free
   roles:
     - iptables
-    - zuul-user
     - sync-project-config
     - install-docker
     - accessbot