Clean up cron tab entry from ansible once removed from host

This is a followup to the previous change that cleans up a now unused
crontab resource. THis should be merged once the actual crontab entry
has been removed from the host.

Change-Id: Ieb8df262d9b047e860a22cfac5569c4ca0b7111b

playbooks/roles/gerrit/tasks/main.yaml

@@ -306,15 +306,6 @@
     minute: 17
     hour: 4
 
-- name: Set up cron job to optmize local mirror git repos
-  cron:
-    name: optmize-local-git-repos
-    state: absent
-    user: gerrit2
-    job: 'find /opt/lib/git/ -type d -name "*.git" -print -exec git --git-dir="{}" gc \;'
-    minute: 17
-    hour: 4
-
 - name: Set up cron job to track upstream
   cron:
     name: track-upstream