chore: update babel monorepo to v7.8.4

Author: renovate-bot

package-lock.json

@@ -89,11 +89,11 @@
     "react-docgen": "^3.0.0 || ^4.0.0 || ^5.0.0-beta || ^5.0.0"
   },
   "devDependencies": {
-    "@babel/cli": "7.8.3",
-    "@babel/core": "7.8.3",
+    "@babel/cli": "7.8.4",
+    "@babel/core": "7.8.4",
     "@babel/plugin-syntax-flow": "7.8.3",
     "@babel/plugin-transform-flow-strip-types": "7.8.3",
-    "@babel/preset-env": "7.8.3",
+    "@babel/preset-env": "7.8.4",
     "@babel/register": "7.8.3",
     "ava": "2.4.0",
     "babel-eslint": "10.0.3",