Fix `tootctl media remove-orphans` ignoring `PAPERCLIP_ROOT_PATH` (#13375)

Fix #13371

lib/mastodon/media_cli.rb

@@ -115,7 +115,7 @@ module Mastodon
       when :filesystem
         require 'find'
 
-        root_path = ENV.fetch('RAILS_ROOT_PATH', File.join(':rails_root', 'public', 'system')).gsub(':rails_root', Rails.root.to_s)
+        root_path = ENV.fetch('PAPERCLIP_ROOT_PATH', File.join(':rails_root', 'public', 'system')).gsub(':rails_root', Rails.root.to_s)
 
         Find.find(File.join(*[root_path, prefix].compact)) do |path|
           next if File.directory?(path)