Issue 50975 - Revise UI branding with new minimized build
    
    Description:  We can no longer use the previous method of text replacement
                  to brand the UI for downstream vs upstream builds.  Instead
                  we can use css files to set the branding, and the specfile
                  can do a text replacement on the non-miminized css file.
    
    fixes: https://pagure.io/389-ds-base/issue/50975
    
    Reviewed by: firstyear & mhonek (Thanks!!)