Bug 1555091 - enable wpt 'kind.html'. r=jya

This test only contains simple API behavior test, which is not possible to be affected by web-render.

Differential Revision: https://phabricator.services.mozilla.com/D32870

--HG--
extra : moz-landing-system : lando

testing/web-platform/meta/html/semantics/embedded-content/media-elements/interfaces/TextTrack/kind.html.ini

@@ -1,3 +0,0 @@
-[kind.html]
-  disabled:
-    if (os == "linux") and webrender: true