Fix platform ruby installation with rubygems

Author: ntkme

ext/sass/Rakefile

@@ -49,7 +49,7 @@ end
 file 'dart-sass/sass' do
   gem_install 'sass-embedded', SassConfig.gem_version, SassConfig.gem_platform do |installer|
     gh_attestation_verify(installer.gem, repo: 'sass-contrib/sass-embedded-host-ruby')
-    mv File.absolute_path('ext/sass/dart-sass', installer.gem_dir), 'dart-sass'
+    mv File.absolute_path('lib/sass/dart-sass', installer.gem_dir), 'dart-sass'
   end
 rescue StandardError
   archive = fetch(SassConfig.dart_sass)