Creating a redirect is missing the site path

[kevincrafts]

When creating a redirect on a launched site, the input field asks for a path to create a redirect from. The issue here is that the prefix they are showing is only www.colorado.edu and does NOT include their site path. This might lead users to include the entire path, including their site path, in the redirect field and this results in a redirect that will not work because the site path would be duplicated.

For example, if a user on the engineering site entered "engineering/undergrad", the redirect would be created for "/engineering/engineering/undergrad"

If they do NOT include their site path, the correct redirect would be created, but the field and prefix make it seem like the site path is required.

[timurtripp]

Issue opened in the Redirect contrib module: #3465080