chore(deps): update dependency react-test-renderer to v16.8.4 (#473)

Author: renovate[bot]

package-lock.json

@@ -62,7 +62,7 @@
     "mini-css-extract-plugin": "0.5.0",
     "node-sass": "4.11.0",
     "postcss-loader": "3.0.0",
-    "react-test-renderer": "16.8.3",
+    "react-test-renderer": "16.8.4",
     "rimraf": "2.6.3",
     "sass-loader": "7.1.0",
     "style-loader": "0.23.1",