Drone get instructed to use http when running gitlab behind haproxy

I’m running gitlab with rancher and using its built-in rancher-lb that terminates ssl.
[https(443)] -> rancher-lb -> [http(80)]-> gitlab

I’ve been looking into logs for hours and hours trying all sorts of different things but it seems that gitlab is telling drone to connect to the same port its request is running on locally (http-80)
What configuration can I set to make it work with external ssl-termination?

Relevant Gitlab configuration:

      gitlab_rails['gitlab_shell_ssh_port'] = "2702"
      gitlab_rails['external_url'] = "https://git.**REDACTED**"
      gitlab_rails['gitlab_https'] = true`

Drone configuration:

    DRONE_GITLAB_URL: https://git.**REDATCTED**
    DRONE_GITLAB: 'true'
    DRONE_OPEN: 'true'
    GIN_MODE: release
    DATABASE_DRIVER: sqlite3
    DATABASE_CONFIG: /var/lib/drone/drone.sqlite
    DRONE_DEBUG: 'true'

Drone logs:

+ git init
Initialized empty Git repository in /drone/src/**REDATCTED**/.git/
+ git remote add origin http://git.**REDATCTED**.git
+ git fetch --no-tags origin +refs/heads/master:
fatal: unable to access 'http://git.**REDATCTED**.git/': The requested URL returned error: 400
exit status 128