add jenkins to hub

docs-ref-conceptual/index.yml

@@ -53,7 +53,7 @@ sections:
   - type: list
     style: cards
     className: cardsM
-    columns: 3
+    columns: 2
     items: 
     - image:
         src: https://docs.microsoft.com/azure/media/index/app-service-web.svg
@@ -67,6 +67,10 @@ sections:
         src: https://docs.microsoft.com/azure/media/index/cosmosdb.svg
       title: Build a web app with Cosmos DB
       href: https://docs.microsoft.com/azure/cosmos-db/create-documentdb-java
+    - image:
+        src: media/jenkins_logo.svg
+      title: CI/CD to App Service
+      href: https://docs.microsoft.com/en-us/azure/jenkins/java-deploy-webapp-tutorial
 - title: Samples
   items:
   - type: list