Bug 1497774 - Remove the nightly dmd task. r=glandium

We no longer need a separate nightly task for dmd since it's now enabled by default in nightly m-c builds.

--HG--
extra : rebase_source : d76a27f839055e7af9467f316d5392c269d66112

.cron.yml

@@ -78,18 +78,6 @@ jobs:
           - {hour: 16, minute: 0}
           - {hour: 4, minute: 0}
 
-    - name: nightly-dmd
-      job:
-          type: decision-task
-          treeherder-symbol: Ndmd
-          target-tasks-method: nightly_dmd
-      run-on-projects:
-          - mozilla-central
-      when:
-          by-project:
-              mozilla-central: [{hour: 10, minute: 0}]
-              # No default
-
     - name: searchfox-index
       job:
           type: decision-task