Feat-Use synk to check cron-job security settings

Use synk to check for cron-job yaml for secuity misconfiguration.

.github/workflows/synk-cron.yaml

@@ -0,0 +1,19 @@
+name: synk-cron-job-check
+on: push
+jobs:
+  snyk:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - name: Run Snyk on cron-job k8s yaml
+        continue-on-error: true
+        uses: snyk/actions/iac@master
+        env:
+          SNYK_TOKEN: ${{ secrets.SNYK_TOKEN }}
+        with:
+          file: k8s/cron.yaml
+          args: --severity-threshold=high
+      - name: Upload result to GitHub Code Scanning
+        uses: github/codeql-action/upload-sarif@v1
+        with:
+          sarif_file: snyk.sarif