Add back timeout for teardown

#2318 removed the timeout code for test teardown.  It should not be needed, but some CI jobs intermittently lock up.  Without it, we can't see which test(s) caused the lock up.

test/helper.rb

@@ -72,7 +72,10 @@ module TimeoutEveryTestCase
 
         Minitest::Test::TEARDOWN_METHODS.each do |hook|
           capture_exceptions do
-            self.send hook
+            # wrap timeout around teardown methods, remove when they're stable
+            ::Timeout.timeout(RUBY_ENGINE == 'ruby' ? 60 : 120, TestTookTooLong) {
+              self.send hook
+            }
           end
         end
       end