adding jenkins file

Jenkinsfile

@@ -0,0 +1,15 @@
+pipeline {
+    agent any
+
+    stages {
+        stage('run frontend') {
+            steps {
+                echo 'executing yarn'
+                nodejs( 'nodejs10.17.0') {
+                  sh 'yarn install'
+                  sh 'yarn build '
+                }
+            }
+        }
+    }
+}