replace _ in aws stacks

Change-Id: I77f09c885bc4063bc4e87dc26088faa5df96fd66
diff --git a/cloud-deploy-pipeline.groovy b/cloud-deploy-pipeline.groovy
index bd7f194..b34db68 100644
--- a/cloud-deploy-pipeline.groovy
+++ b/cloud-deploy-pipeline.groovy
@@ -135,12 +135,14 @@
                             } else {
                                 STACK_NAME = "jenkins-${JOB_NAME}-${BUILD_NUMBER}"
                             }
-                            currentBuild.description = STACK_NAME
                         }
+
+                        // no underscore in STACK_NAME
+                        STACK_NAME = STACK_NAME.replaceAll('_', '-')
                     }
 
                     // set description
-                    currentBuild.description = "${STACK_NAME}"
+                    currentBuild.description = STACK_NAME
 
                     // prepare configuration
                     def env_vars = aws.getEnvVars(AWS_API_CREDENTIALS, AWS_STACK_REGION)