replace underscore with dash in helm chart name

Jenkinsfile

@@ -362,7 +362,7 @@ String generateHelmChartVersion() {
         chartVersion += "-${env.BRANCH_NAME}"
     }
 
-    return chartVersion
+    return chartVersion.replaceAll("_", "-")
 }
 
 Void tagAndPushDockerImage(String newTag){