Bug 1510441: Add `.cron.yml` to the taskgraph sparse profile; r=gps

Differential Revision: https://phabricator.services.mozilla.com/D13142

--HG--
extra : moz-landing-system : lando

build/sparse-profiles/taskgraph

@@ -48,3 +48,4 @@ glob:**/*.gradle
 
 # for action-task building
 path:.taskcluster.yml
+path:.cron.yml