Http Proxy "Test connection" with the correct username and password leads to 407 error

1. In the Satellite web UI, navigate to Infrastructure > HTTP Proxies.
2. Click New HTTP Proxy.
3. In the Name field, enter the name for the HTTP proxy.
4. In the Url field, enter the URL of the HTTP proxy in the following format: https://proxy.example.com:8080.
5. Optional: If authentication is required, in the Username field, enter the username to authenticate with.
6. Optional: If authentication is required, in the Password field, enter the password to authenticate with.
7. To test connection to the proxy, click the Test Connection button.