Bump @babel/core from 7.7.7 to 7.8.4

Bumps [@babel/core](https://github.com/babel/babel) from 7.7.7 to 7.8.4.
- [Release notes](https://github.com/babel/babel/releases)
- [Changelog](https://github.com/babel/babel/blob/master/CHANGELOG.md)
- [Commits](babel/babel@v7.7.7...v7.8.4)

Signed-off-by: dependabot-preview[bot] <support@dependabot.com>

package.json

@@ -64,7 +64,7 @@
   },
   "devDependencies": {
     "@babel/cli": "^7.8.4",
-    "@babel/core": "^7.7.7",
+    "@babel/core": "^7.8.4",
     "@babel/preset-env": "^7.8.4",
     "@sentry/webpack-plugin": "^1.10.0",
     "@types/jest": "^24.0.25",