remove ugly stack trace from netrc file not existing

Author: ssadedin

src/main/groovy/bpipe/notification/HTTPNotificationChannel.groovy

@@ -198,7 +198,6 @@ class HTTPNotificationChannel implements NotificationChannel {
             }
             catch(Exception e) {
                 log.warning("Failed to load netrc file: " + e)
-                e.printStackTrace()
                 this.netrc = new NetRC(hosts:[])
             }
         }