audit: update mirrorservice check

mirrorservice accepts `http://ftp.mirrorservice.org` as well, apparently.

Library/Homebrew/cmd/audit.rb

@@ -1160,13 +1160,13 @@ class ResourceAuditor
            %r{^http://mirrors\.kernel\.org/},
            %r{^http://(?:[^/]*\.)?bintray\.com/},
            %r{^http://tools\.ietf\.org/},
-           %r{^http://www\.mirrorservice\.org/},
            %r{^http://launchpad\.net/},
            %r{^http://bitbucket\.org/},
            %r{^http://cpan\.metacpan\.org/},
            %r{^http://hackage\.haskell\.org/},
            %r{^http://(?:[^/]*\.)?archive\.org},
-           %r{^http://(?:[^/]*\.)?freedesktop\.org}
+           %r{^http://(?:[^/]*\.)?freedesktop\.org},
+           %r{^http://(?:[^/]*\.)?mirrorservice\.org/}
         problem "Please use https:// for #{p}"
       when %r{^http://search\.mcpan\.org/CPAN/(.*)}i
         problem "#{p} should be `https://cpan.metacpan.org/#{$1}`"