Add alpine based pvc example

generic/alpine-pvc-block.yaml

@@ -0,0 +1,31 @@
+apiVersion: v1
+kind: Pod
+metadata:
+  name: alpine-sleep
+spec:
+  containers:
+  - name: busybox
+    image: alpine:3.14
+    args:
+    - sleep
+    - "1000000"
+    volumeMounts:
+      - mountPath: /data
+        name: alpine-data
+  volumes:
+    - name: alpine-data
+      persistentVolumeClaim:
+        claimName: alpine-data-rbd
+
+---
+kind: PersistentVolumeClaim
+apiVersion: v1
+metadata:
+  name: alpine-data-rbd
+spec:
+  accessModes:
+    - ReadWriteOnce
+  resources:
+    requests:
+      storage: 1Gi
+  storageClassName: rook-ceph-block