Use credentials for pre-emptive Basic authentication
Use credentials for pre-emptive Basic authentication

If the username and password have been set a Basic authentication header
is set pre-emptively. The Jenkins server doesn't send any authentication
request but needs the necessary header in place right in the first
request.

I couldn't find any other way to do pre-emptive authentication with Soup
than setting the correct header directly.

backuity/cinnamon-jenkins-applet,backuity/cinnamon-jenkins-applet