Updated jenkins file

Jenkinsfile

@@ -1,8 +1,21 @@
 pipeline {
     agent any
     stages {
+		stage('build') {
+			agent {
+				docker {
+					image 'rust'
+					reuseNode true
+				}
+			}
+			steps {
+				sh 'cargo build --release'
+				stash includes: 'target/release/rollux', name: 'app'
+			}
+		}
 		stage('docker build') {
 			steps {
+				unstash 'app'
 				echo 'Starting docker image build'
 				script {
 					docker.withRegistry("https://pkg.northcode.no", 'docker-login') {