Adds readinessProbe and livenessProbe to prometheus-adapter jsonnet

Problem: Currently the prometheus-adapter pods are restarted at the same
time even though the deployment is configured with strategy RollingUpdate.
This happens because the kubelet does not know when the prometheus-adapter
pods are ready to start receiving requests.

Solution: Add both readinessProbe and livenessProbe to the
prometheus-adapter, this way the kubelet will know when either the pod
stoped working and should be restarted or simply when it ready to start
receiving requests.

Issue: https://bugzilla.redhat.com/show_bug.cgi?id=2048333

jsonnet/kube-prometheus/components/prometheus-adapter.libsonnet

@@ -10,6 +10,30 @@ local defaults = {
     requests: { cpu: '102m', memory: '180Mi' },
     limits: { cpu: '250m', memory: '180Mi' },
   },
+  livenessProbe:: {
+    livenessProbe: {
+      httpGet: {
+        path: '/healthz',
+        port: 'https',
+        scheme: 'HTTPS',
+      },
+      initialDelaySeconds: 5,
+      periodSeconds: 30,
+      failureThreshold: 5,
+    },
+  },
+  readinessProbe:: {
+    readinessProbe: {
+      httpGet: {
+        path: '/healthz',
+        port: 'https',
+        scheme: 'HTTPS',
+      },
+      initialDelaySeconds: 5,
+      periodSeconds: 5,
+      failureThreshold: 5,
+    },
+  },
   replicas:: 2,
   listenAddress:: '127.0.0.1',
   port:: 9100,
@@ -220,6 +244,8 @@ function(params) {
         '--tls-cipher-suites=' + std.join(',', pa._config.tlsCipherSuites),
       ],
       resources: pa._config.resources,
+      readinessProbe: pa._config.readinessProbe,
+      livenessProbe: pa._config.livenessProbe,
       ports: [{ containerPort: 6443 }],
       volumeMounts: [
         { name: 'tmpfs', mountPath: '/tmp', readOnly: false },