Build failure with jruby

[oliverklee]

The current master fails on jruby-9.1.8.0:
https://travis-ci.org/haml/html2haml/jobs/219907278

The failure is due to one test failing:

Html2HamlTest#test_style_to_css_filter_with_following_content [/home/travis/build/haml/html2haml/test/jruby/html2haml_test.rb:53]:
--- expected
+++ actual
@@ -3,5 +3,4 @@
     foo {
         bar: baz;
     }
-%body
-  Hello"
+%body Hello"

The build for the other Rubies is green.