Bug 1381892 - Disable wpt box-sizing-replaced-001.xht for instability, a=testonly

MozReview-Commit-ID: 4kt5SxkaQ0T

testing/web-platform/meta/css/vendor-imports/mozilla/mozilla-central-reftests/ui3/box-sizing-replaced-001.xht.ini

@@ -1,5 +1,6 @@
 [box-sizing-replaced-001.xht]
   type: reftest
+  disabled: https://bugzilla.mozilla.org/show_bug.cgi?id=1381892
   expected:
     if not debug and not e10s and (os == "linux") and (version == "Ubuntu 16.04") and (processor == "x86_64") and (bits == 64): FAIL
     if not debug and e10s and (os == "linux") and (version == "Ubuntu 16.04") and (processor == "x86_64") and (bits == 64): FAIL