- update gitea Jenkinsfile to update instead of create stack if stack exists

dockerfiles/services/gitea/Jenkinsfile

@@ -8,13 +8,19 @@ node('docker') {
 
     stage('build') {
         dir(workdir) {
-            //nothing to do
+            sh "DOCKER_HOST=dkhost:2376 docker-compose -f docker-compose.yml pull"
         }
     }
 
     stage('deploy') {
         dir(workdir) {
-            sh "DOCKER_HOST=dkhost:2376 docker stack deploy -c docker-compose.yml gitea"
+            sh '''export DOCKER_HOST=dkhost:2376
+
+            if docker stack ls | grep gitea; then
+              docker service update gitea_app
+            else
+              docker stack deploy -c docker-compose.yml gitea
+            fi'''
         }
     }