Update dependency @babel/standalone to v7.7.4 (reactjs#965)

Author: renovate[bot]

src/React.Core/package-lock.json

@@ -7,7 +7,7 @@
   },
   "devDependencies": {
     "@babel/core": "7.6.4",
-    "@babel/standalone": "7.6.4",
+    "@babel/standalone": "7.7.4",
     "prop-types": "15.7.2",
     "react": "16.10.2",
     "react-dom": "16.10.2",