update kuber doc

Containerization & Orchestration/Kubernetes/workloads/08-Cronjobs.md

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+# ⏰ Kubernetes CronJobs
+
+A **CronJob** in Kubernetes allows you to run jobs on a recurring schedule, similar to traditional UNIX `cron` jobs. Ideal for periodic tasks like backups, reports, or scheduled notifications.
+
+---
+
+## 🔍 CronJob Commands
+
+### 📄 List CronJobs in a Namespace
+```bash
+kubectl get cronjobs.batch -n <namespace>
+````
+
+### ❌ Delete a CronJob
+
+```bash
+kubectl delete cronjobs.batch -n <namespace> <cronjob-name>
+```
+
+---
+
+## 🧾 Example CronJob Manifest
+
+This CronJob runs every minute and prints the date followed by "Kubernetes":
+
+```yaml
+apiVersion: batch/v1
+kind: CronJob
+metadata:
+  name: cronjob1
+  namespace: ns
+spec:
+  schedule: "* * * * *"
+  jobTemplate:
+    spec:
+      template:
+        spec:
+          containers:
+            - name: cronjob
+              image: debian:bookworm
+              command:
+                - /bin/bash
+                - -c
+                - date; echo Kubernetes
+          restartPolicy: Never
+```
+
+> 🛠 **Fix:** Changed `JobTemplate` to `jobTemplate` (YAML keys are case-sensitive).
+> 🕐 The `schedule` field follows standard cron format: `minute hour day-of-month month day-of-week`.
+> 🧠 **Tip:** Always test cron timing carefully to avoid unintentional frequent runs.
+