Scout contains an Open Redirect on Login via `next`

Scout is a web-based visualizer for VCF-files. Open redirect vulnerability allows performing phishing attacks on users by redirecting them to malicious page. /login API endpoint is vulnerable to open redirect attack via next parameter due to absence of sanitization logic. Additionally, due to lack of scheme validation, HTTPS Downgrade Attack can be performed on the users. This vulnerability is fixed in 4.89.