add documentation for grafana pod resource

docs/guides/prerequisites/PodUsageInGrafana.md

+# How to monitor Pod Resource using Grafana
+
+1. Log in to Grafana url with credentials \
+    To Get Grafana credentals: \
+    Username:
+    ```
+    kubectl get  secret monitoring-monitoring-grafana  -o jsonpath='{.data.admin-user}' | base64 -d
+    ```
+    Password:
+    ```
+    kubectl get  secret monitoring-monitoring-grafana  -o jsonpath='{.data.admin-password}' | base64 -d
+    ```
+    Or [review password value within helm chart](https://repo1.dso.mil/platform-one/big-bang/apps/core/monitoring/-/blob/main/chart/values.yaml#L708)
+
+2.  Once logged in and directed to the home page, click  the menu Dashboard and then select  Manage. \
+     ![Manage Dashboard Screenshot](docs/guides/prerequisites/grafana-dashboard-manage.jpeg)
+3.  From the Dashboard  select Kubernetes/Compute Resource / Pod . \
+     This creates a dashboard to monitor the pod resource CPU Usage, CPU Throttling, CPU quota, Memory Usage, Memory Quota, etc. \
+     ![Pod Resource Grafana Screenshot](docs/guides/prerequisites/grafana-dashboard.jpeg)
+