jenkins: update to 2.568.1 LTS and chart

Change-Id: Ib6b48599a09dee669d77441c12b354240ef257b8
diff --git a/charts/jenkins/Chart.yaml b/charts/jenkins/Chart.yaml
index 2a42c71..0b64f7f 100644
--- a/charts/jenkins/Chart.yaml
+++ b/charts/jenkins/Chart.yaml
@@ -1,14 +1,14 @@
 annotations:
   artifacthub.io/category: integration-delivery
   artifacthub.io/changes: |
-    - Fix Prometheus controller name.
+    - Evaluate `tpl` on `agent.image.registry`, `agent.image.repository`, and `agent.image.tag` so the default kubernetes-agent pod template can compose its jnlp image from other Helm values or named templates. Complements the `tpl`-support added for `controller.javaOpts` / `controller.jenkinsOpts` in 5.9.39.
   artifacthub.io/images: |
     - name: jenkins
-      image: docker.io/jenkins/jenkins:2.440.2-jdk17
+      image: docker.io/jenkins/jenkins:2.568.1-jdk21
     - name: k8s-sidecar
-      image: docker.io/kiwigrid/k8s-sidecar:1.26.1
+      image: docker.io/kiwigrid/k8s-sidecar:2.8.1
     - name: inbound-agent
-      image: jenkins/inbound-agent:3206.vb_15dcf73f6a_9-3
+      image: jenkins/inbound-agent:3383.vc8881d4b_0e76-1
   artifacthub.io/license: Apache-2.0
   artifacthub.io/links: |
     - name: Chart Source
@@ -18,9 +18,9 @@
     - name: support
       url: https://github.com/jenkinsci/helm-charts/issues
 apiVersion: v2
-appVersion: 2.440.2
+appVersion: 2.568.1
 description: 'Jenkins - Build great things at any scale! As the leading open source
-  automation server, Jenkins provides over 1800 plugins to support building, deploying
+  automation server, Jenkins provides over 2000 plugins to support building, deploying
   and automating any project. '
 home: https://www.jenkins.io/
 icon: https://get.jenkins.io/art/jenkins-logo/logo.svg
@@ -42,8 +42,8 @@
 name: jenkins
 sources:
 - https://github.com/jenkinsci/jenkins
-- https://github.com/jenkinsci/docker-inbound-agent
+- https://github.com/jenkinsci/docker-agent
 - https://github.com/maorfr/kube-tasks
 - https://github.com/jenkinsci/configuration-as-code-plugin
 type: application
-version: 5.1.5
+version: 5.9.40