capture possible cdn host

in production environments the url_prefix may be proceeded by a cdn host, ensure that it is part of the capture group
this change will require anything prior to the url_prefix to end in a forward slash

Author: tagCincy

lib/propshaft/compiler/source_mapping_urls.rb

@@ -11,7 +11,7 @@ def compile(logical_path, input)
 
   private
     def asset_path(source_mapping_url, logical_path)
-      source_mapping_url.gsub!(/^\/?#{url_prefix}\//, "")
+      source_mapping_url.gsub!(/^(.+\/)?#{url_prefix}\//, "")
 
       if logical_path.dirname.to_s == "."
         source_mapping_url