chore: Change stalebot rules (kubeflow#10547)

daysUntilClose is set to 90 days. This is too much for an issue to keep opened as there is daysUntilStale set to 90 days.
That would keep an issue opened for 6 months, and now there are +600 issues opened in the repository.

We need to start working on keeping the repository healthy.

Signed-off-by: Ricardo M. Oliveira <rmartine@redhat.com>

.github/stale.yml

@@ -2,9 +2,9 @@
 # https://probot.github.io/apps/stale/
 #
 # Number of days of inactivity before an issue becomes stale
-daysUntilStale: 90
+daysUntilStale: 60
 # Number of days of inactivity before a stale issue is closed
-daysUntilClose: 90
+daysUntilClose: 21
 # Issues with these labels will never be considered stale
 exemptLabels:
   - lifecycle/frozen

.github/workflows/stale.yml

@@ -21,10 +21,8 @@ jobs:
     - uses: actions/stale@v5
       with:
         repo-token: ${{ secrets.GITHUB_TOKEN }}
-        days-before-stale: -1
-        days-before-close: -1
-        days-before-issue-stale: 90
-        days-before-issue-close: 90
+        days-before-stale: 60
+        days-before-close: 21
         stale-issue-message: >
           This issue has been automatically marked as stale because it has not had
           recent activity. It will be closed if no further activity occurs. Thank you