cask-tests: re-add removed comment

Library/Homebrew/cask/cmd/brew-cask-tests.rb

@@ -16,7 +16,10 @@ repo_root.cd do
   rspec = ARGV.flag?("--rspec") || !ARGV.flag?("--minitest")
   minitest = ARGV.flag?("--minitest") || !ARGV.flag?("--rspec")
 
+  # TODO: setting the --seed here is an ugly temporary hack, to remain only
+  #       until test-suite glitches are fixed.
   ENV["TESTOPTS"] = "--seed=14830" if ENV["TRAVIS"]
+
   ENV["HOMEBREW_TESTS_COVERAGE"] = "1" if ARGV.flag?("--coverage")
 
   if rspec