probot: Increase days of inactivity

.github/stale.yml

@@ -1,17 +1,17 @@
 # Number of days of inactivity before an issue becomes stale
-daysUntilStale: 21
+daysUntilStale: 60
 # Number of days of inactivity before a stale issue is closed
 daysUntilClose: 7
 # Issues with these labels will never be considered stale
 exemptLabels:
+  - discussion
   - pinned
-  - security
 # Label to use when marking an issue as stale
 staleLabel: on hiatus
 # Comment to post when marking an issue as stale. Set to `false` to disable
 markComment: >
-  This issue has been automatically marked as `on hiatus because it has not had
+  This issue has been automatically marked as `on hiatus` because it has not had
   recent activity. It will be closed if no further activity occurs. Thank you
   for your contributions.
 # Comment to post when closing a stale issue. Set to `false` to disable
-closeComment: false
+closeComment: false