ci: collect memcached metrics (#7410)

* ci: collect memcached metrics

* ci: use nobody/nobody for metrics container

k8s/memcached.yaml

@@ -16,6 +16,21 @@ spec:
       securityContext:
         runAsNonRoot: true
       containers:
+        - image: "quay.io/prometheus/memcached-exporter:v0.14.3"
+          imagePullPolicy: IfNotPresent
+          name: memcached-exporter
+          ports:
+            - name: metrics
+              containerPort: 9150
+              protocol: TCP
+          securityContext:
+            allowPrivilegeEscalation: false
+            capabilities:
+              drop:
+                - ALL
+            readOnlyRootFilesystem: true
+            runAsUser: 65534  # nobody
+            runAsGroup: 65534  # nobody
         - image: "memcached:1.6-alpine"
           imagePullPolicy: IfNotPresent
           args: ["-m", "1024"]
@@ -41,6 +56,8 @@ apiVersion: v1
 kind: Service
 metadata:
   name: memcached
+  annotations:
+    k8s.grafana.com/scrape: "yes"
 spec:
   type: ClusterIP
   ports:
@@ -48,5 +65,9 @@ spec:
       targetPort: memcached
       protocol: TCP
       name: memcached
+    - port: 9150
+      targetPort: metrics
+      protocol: TCP
+      name: metrics
   selector:
     app: memcached