Update to java 21, 1.21 with cosmso

Jenkinsfile

@@ -0,0 +1,24 @@
+pipeline {
+    agent any
+    stages {
+        stage('Gradle') {
+            steps {
+                sh '''
+                  set +x
+                  chmod +x gradlew
+                  ./gradlew build
+                '''
+            }
+        }
+        stage('Archive') {
+            steps {
+                archiveArtifacts artifacts: 'build/libs/', followSymlinks: false
+            }
+        }
+        stage('discord') {
+            steps {
+                discordSend description: "Build: ${BUILD_NUMBER}", showChangeset: true, result: currentBuild.currentResult, title: currentBuild.fullProjectName, webhookURL: env.discordwebhook
+            }
+        }
+    }
+}