Update Jenkinsfile

Jenkinsfile

@@ -7,5 +7,17 @@ pipeline {
                 sh './mvnw package
             }
         }           
+    stage('Build Docker Image') {
+         when {
+             branch 'main'
+         }
+         steps {
+             script {
+                 app = docker.build("sprientera/pets")
+                 app.inside {
+                   sh 'echo $(curl localhost:80)'
+                 }
+             }
+         }     
+     }
  }
-}