Revert "CI: Increase nightly CI check window to 14 days. (#6628)" (#6660)

This reverts commit 4ea180a.

Authors:
  - Simon Adorf (https://github.com/csadorf)

Approvers:
  - James Lamb (https://github.com/jameslamb)

URL: #6660

Author: csadorf

.github/workflows/pr.yaml

@@ -58,7 +58,6 @@ jobs:
         uses: rapidsai/shared-actions/check_nightly_success/dispatch@main
         with:
           repo: cuml
-          max_days_without_success: 14
   changed-files:
     secrets: inherit
     needs: telemetry-setup