helm dep update command returning 404

Charts.gitlab.io returning 404

$ helm dev update gitlab
...
Hang tight while we grab the latest from your chart repositories...
...Unable to get an update from the "local" chart repository (http://127.0.0.1:8879/charts):
        Get http://127.0.0.1:8879/charts/index.yaml: dial tcp 127.0.0.1:8879: getsockopt: connection refused
...Successfully got an update from the "es-operator" chart repository
...Unable to get an update from the "gitlab" chart repository (https://charts.gitlab.io):
        Failed to fetch https://charts.gitlab.io/index.yaml : 404 Not Found

$ curl -I  https://charts.gitlab.io/index.yaml
HTTP/2 404 
content-type: text/html; charset=utf-8
x-content-type-options: nosniff
content-length: 3067
date: Mon, 02 Jul 2018 06:52:55 GMT