Enhance daily CI workflow with failure notifications

Added a notification job for failed daily CI runs.

Author: rishav-karanjit

.github/workflows/daily_ci.yml

@@ -4,9 +4,22 @@ name: Daily CI
 on:
   schedule:
     - cron: "00 15 * * 1-5"
-
+  pull_request:
+    paths:
+      .github/workflows/daily_ci.yml
 jobs:
   DAILY_CI:
     # Don't run the cron builds on forks
     if: github.event_name != 'schedule' || github.repository_owner == 'aws'
-    uses: ./.github/workflows/ci.yml
+    uses: ./.github/workflows/ci.yml
+  notify:
+    needs:
+      [
+        DAILY_CI
+      ]
+    if: ${{ failure() && github.event_name != 'schedule'}}
+    uses: ./.github/workflows/slack-notification.yml
+    with:
+      message: "Daily CI failed on `${{ github.repository }}`. View run: ${{ github.server_url }}/${{ github.repository }}/actions/runs/${{ github.run_id }}"
+    secrets:
+      SLACK_WEBHOOK_URL: ${{ secrets.SLACK_WEBHOOK_URL_CI }}