Upgrade test dependencies
diff --git a/package.json b/package.json
index 35a2ed1..e0ff33f 100644
--- a/package.json
+++ b/package.json
@@ -58,7 +58,7 @@
     "husky": "^3.0.7",
     "lerna": "^3.16.4",
     "lint-staged": "^9.4.0",
-    "mocha": "^6.2.0",
+    "mocha": "^6.2.2",
     "mocha-loader": "^3.0.0",
     "multi-entry-loader": "^1.1.2",
     "node-fetch": "^2.5.0",
diff --git a/yarn.lock b/yarn.lock
index 6ef7d37..35e8f08 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -5855,7 +5855,7 @@
   resolved "https://registry.yarnpkg.com/lodash.uniq/-/lodash.uniq-4.5.0.tgz#d0225373aeb652adc1bc82e4945339a842754773"
   integrity sha1-0CJTc662Uq3BvILklFM5qEJ1R3M=
 
-lodash@^4.17.11, lodash@^4.17.12, lodash@^4.17.13, lodash@^4.17.14, lodash@^4.2.1:
+lodash@^4.17.11, lodash@^4.17.12, lodash@^4.17.13, lodash@^4.17.14, lodash@^4.17.15, lodash@^4.2.1:
   version "4.17.15"
   resolved "https://registry.yarnpkg.com/lodash/-/lodash-4.17.15.tgz#b447f6670a0455bbfeedd11392eff330ea097548"
   integrity sha512-8xOcRHvCjnocdS5cpwXQXVzmmh5e5+saE2QGoeQmbKmRS6J3VQppPOIt0MnmE+4xlZoumy0GPG0D0MVIQbNA1A==
@@ -6284,10 +6284,10 @@
     script-loader "^0.7.2"
     style-loader "^1.0.0"
 
-mocha@^6.2.0:
-  version "6.2.0"
-  resolved "https://registry.yarnpkg.com/mocha/-/mocha-6.2.0.tgz#f896b642843445d1bb8bca60eabd9206b8916e56"
-  integrity sha512-qwfFgY+7EKAAUAdv7VYMZQknI7YJSGesxHyhn6qD52DV8UcSZs5XwCifcZGMVIE4a5fbmhvbotxC0DLQ0oKohQ==
+mocha@^6.2.2:
+  version "6.2.2"
+  resolved "https://registry.yarnpkg.com/mocha/-/mocha-6.2.2.tgz#5d8987e28940caf8957a7d7664b910dc5b2fea20"
+  integrity sha512-FgDS9Re79yU1xz5d+C4rv1G7QagNGHZ+iXF81hO8zY35YZZcLEsJVfFolfsqKFWunATEvNzMK0r/CwWd/szO9A==
   dependencies:
     ansi-colors "3.2.3"
     browser-stdout "1.3.1"
@@ -6309,9 +6309,9 @@
     supports-color "6.0.0"
     which "1.3.1"
     wide-align "1.1.3"
-    yargs "13.2.2"
-    yargs-parser "13.0.0"
-    yargs-unparser "1.5.0"
+    yargs "13.3.0"
+    yargs-parser "13.1.1"
+    yargs-unparser "1.6.0"
 
 modify-values@^1.0.0:
   version "1.0.1"
@@ -9544,10 +9544,10 @@
   resolved "https://registry.yarnpkg.com/yallist/-/yallist-3.1.0.tgz#906cc2100972dc2625ae78f566a2577230a1d6f7"
   integrity sha512-6gpP93MR+VOOehKbCPchro3wFZNSNmek8A2kbkOAZLIZAYx1KP/zAqwO0sOHi3xJEb+UBz8NaYt/17UNit1Q9w==
 
-yargs-parser@13.0.0:
-  version "13.0.0"
-  resolved "https://registry.yarnpkg.com/yargs-parser/-/yargs-parser-13.0.0.tgz#3fc44f3e76a8bdb1cc3602e860108602e5ccde8b"
-  integrity sha512-w2LXjoL8oRdRQN+hOyppuXs+V/fVAYtpcrRxZuF7Kt/Oc+Jr2uAcVntaUTNT6w5ihoWfFDpNY8CPx1QskxZ/pw==
+yargs-parser@13.1.1, yargs-parser@^13.0.0, yargs-parser@^13.1.0, yargs-parser@^13.1.1:
+  version "13.1.1"
+  resolved "https://registry.yarnpkg.com/yargs-parser/-/yargs-parser-13.1.1.tgz#d26058532aa06d365fe091f6a1fc06b2f7e5eca0"
+  integrity sha512-oVAVsHz6uFrg3XQheFII8ESO2ssAf9luWuAd6Wexsu4F3OtIW0o8IribPXYrD4WC24LWtPrJlGy87y5udK+dxQ==
   dependencies:
     camelcase "^5.0.0"
     decamelize "^1.2.0"
@@ -9560,24 +9560,16 @@
     camelcase "^5.0.0"
     decamelize "^1.2.0"
 
-yargs-parser@^13.0.0, yargs-parser@^13.1.0, yargs-parser@^13.1.1:
-  version "13.1.1"
-  resolved "https://registry.yarnpkg.com/yargs-parser/-/yargs-parser-13.1.1.tgz#d26058532aa06d365fe091f6a1fc06b2f7e5eca0"
-  integrity sha512-oVAVsHz6uFrg3XQheFII8ESO2ssAf9luWuAd6Wexsu4F3OtIW0o8IribPXYrD4WC24LWtPrJlGy87y5udK+dxQ==
-  dependencies:
-    camelcase "^5.0.0"
-    decamelize "^1.2.0"
-
-yargs-unparser@1.5.0:
-  version "1.5.0"
-  resolved "https://registry.yarnpkg.com/yargs-unparser/-/yargs-unparser-1.5.0.tgz#f2bb2a7e83cbc87bb95c8e572828a06c9add6e0d"
-  integrity sha512-HK25qidFTCVuj/D1VfNiEndpLIeJN78aqgR23nL3y4N0U/91cOAzqfHlF8n2BvoNDcZmJKin3ddNSvOxSr8flw==
+yargs-unparser@1.6.0:
+  version "1.6.0"
+  resolved "https://registry.yarnpkg.com/yargs-unparser/-/yargs-unparser-1.6.0.tgz#ef25c2c769ff6bd09e4b0f9d7c605fb27846ea9f"
+  integrity sha512-W9tKgmSn0DpSatfri0nx52Joq5hVXgeLiqR/5G0sZNDoLZFOr/xjBUDcShCOGNsBnEMNo1KAMBkTej1Hm62HTw==
   dependencies:
     flat "^4.1.0"
-    lodash "^4.17.11"
-    yargs "^12.0.5"
+    lodash "^4.17.15"
+    yargs "^13.3.0"
 
-yargs@12.0.5, yargs@^12.0.1, yargs@^12.0.5:
+yargs@12.0.5, yargs@^12.0.1:
   version "12.0.5"
   resolved "https://registry.yarnpkg.com/yargs/-/yargs-12.0.5.tgz#05f5997b609647b64f66b81e3b4b10a368e7ad13"
   integrity sha512-Lhz8TLaYnxq/2ObqHDql8dX8CJi97oHxrjUcYtzKbbykPtVW9WB+poxI+NM2UIzsMgNCZTIf0AQwsjK5yMAqZw==
@@ -9595,23 +9587,6 @@
     y18n "^3.2.1 || ^4.0.0"
     yargs-parser "^11.1.1"
 
-yargs@13.2.2:
-  version "13.2.2"
-  resolved "https://registry.yarnpkg.com/yargs/-/yargs-13.2.2.tgz#0c101f580ae95cea7f39d927e7770e3fdc97f993"
-  integrity sha512-WyEoxgyTD3w5XRpAQNYUB9ycVH/PQrToaTXdYXRdOXvEy1l19br+VJsc0vcO8PTGg5ro/l/GY7F/JMEBmI0BxA==
-  dependencies:
-    cliui "^4.0.0"
-    find-up "^3.0.0"
-    get-caller-file "^2.0.1"
-    os-locale "^3.1.0"
-    require-directory "^2.1.1"
-    require-main-filename "^2.0.0"
-    set-blocking "^2.0.0"
-    string-width "^3.0.0"
-    which-module "^2.0.0"
-    y18n "^4.0.0"
-    yargs-parser "^13.0.0"
-
 yargs@13.2.4:
   version "13.2.4"
   resolved "https://registry.yarnpkg.com/yargs/-/yargs-13.2.4.tgz#0b562b794016eb9651b98bd37acf364aa5d6dc83"
@@ -9629,7 +9604,7 @@
     y18n "^4.0.0"
     yargs-parser "^13.1.0"
 
-yargs@^13.2.2:
+yargs@13.3.0, yargs@^13.2.2, yargs@^13.3.0:
   version "13.3.0"
   resolved "https://registry.yarnpkg.com/yargs/-/yargs-13.3.0.tgz#4c657a55e07e5f2cf947f8a366567c04a0dedc83"
   integrity sha512-2eehun/8ALW8TLoIl7MVaRUrg+yCnenu8B4kBlRxj3GJGDKU1Og7sMXPNm1BYyM1DOJmTZ4YeN/Nwxv+8XJsUA==