Jenkins: add dark theme via simple-theme-plugin

services/jenkins/helmrelease.yaml

@@ -50,6 +50,7 @@ spec:
         - oic-auth
         - job-dsl
         - configuration-as-code-support
+        - simple-theme-plugin
       containerEnv:
         - name: ENABLE_OIDC
           value: "true"
@@ -287,6 +288,11 @@ spec:
                       }
                     }
                   }
+          theme.yaml: |
+            unclassified:
+              simple-theme-plugin:
+                elements:
+                  - cssUrl: "https://jenkins-contrib-themes.github.io/jenkins-material-theme/dist/material-ocean.css"
                   pipelineJob('bstein-dev-home') {
                     triggers {
                       scm('H/2 * * * *')