[npm] upgrade mocha to include mochajs/mocha#3346

(cherry picked from commit a5d1f1c)

Author: spalger

package.json

@@ -282,7 +282,7 @@
     "load-grunt-config": "0.19.2",
     "makelogs": "^4.0.4",
     "marked-text-renderer": "0.1.0",
-    "mocha": "^5.0.5",
+    "mocha": "github:elastic/mocha#37dc027261b2974aa0411955a06c93fb8ed2c06e",
     "mock-fs": "^4.4.2",
     "murmurhash3js": "3.0.1",
     "ncp": "2.0.0",

yarn.lock

@@ -8368,9 +8368,9 @@ mkdirp@^0.3.5, mkdirp@~0.3.5:
   version "0.3.5"
   resolved "https://registry.yarnpkg.com/mkdirp/-/mkdirp-0.3.5.tgz#de3e5f8961c88c787ee1368df849ac4413eca8d7"
 
-mocha@^5.0.5:
+"mocha@github:elastic/mocha#37dc027261b2974aa0411955a06c93fb8ed2c06e":
   version "5.1.1"
-  resolved "https://registry.yarnpkg.com/mocha/-/mocha-5.1.1.tgz#b774c75609dac05eb48f4d9ba1d827b97fde8a7b"
+  resolved "https://codeload.github.com/elastic/mocha/tar.gz/37dc027261b2974aa0411955a06c93fb8ed2c06e"
   dependencies:
     browser-stdout "1.3.1"
     commander "2.11.0"