Bug 1622348 - Enable promise-rejection-events.html wpt back on linux-opt-fission; r=smaug

Differential Revision: https://phabricator.services.mozilla.com/D67870

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

testing/web-platform/meta/html/webappapis/scripting/processing-model-2/unhandled-promise-rejections/promise-rejection-events.html.ini

@@ -1,8 +0,0 @@
-[promise-rejection-events.html]
-  expected:
-    if (os == "linux") and webrender and not debug and fission: ["OK", "TIMEOUT"]
-    if (os == 'linux' and os_version == '18.04') and not debug and fission: ["OK", "TIMEOUT"]  # Bug 1607867
-  [rejectionhandled is dispatched from a queued task, and not immediately]
-    expected:
-      if (os == "linux") and webrender and not debug and fission: ["PASS", "TIMEOUT"]
-