Client OAuth2 login page wrongly redirected with https scheme

## Describe the bug
I'm trying to add my deployment to owncloud desktop, and finally succeeded, but a problem occurred (previously reported as owncloud/client#12242 by @jlssmt)

## Steps to reproduce
1. Deploy ocis
2. Install owncloud desktop
3. Try logging in with oauth2 in browser

## Expected behavior
Log in normally

## Actual behavior
Browser is redirected to **https**://127.0.0.1:/... , which is obviously not accessible, reporting ERR_SSL_PROTOCOL_ERROR (or SSL_ERROR_RX_RECORD_TOO_LONG in firefox)

## Setup
Please describe how you started the server and provide a list of relevant environment variables or configuration files.

```console
(Will add later)
```

## Additional context
I solved this by changing `https://` to `http://` in address bar and press enter. This should be handled by owncloud. I'm not sure if this issue should be in owncloud/ocis, owncloud/web or owncloud/client.