Bump @babel/polyfill from 7.6.0 to 7.7.0 (#52)

Bumps [@babel/polyfill](https://github.com/babel/babel) from 7.6.0 to 7.7.0.
- [Release notes](https://github.com/babel/babel/releases)
- [Changelog](https://github.com/babel/babel/blob/master/CHANGELOG.md)
- [Commits](https://github.com/babel/babel/compare/v7.6.0...v7.7.0)

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

package.json

@@ -16,7 +16,7 @@
     "test:watch": "node_modules/.bin/jest --watch"
   },
   "dependencies": {
-    "@babel/polyfill": "^7.4.0",
+    "@babel/polyfill": "^7.7.0",
     "axios": "^0.19.0",
     "classnames": "^2.2.6",
     "date-fns": "^2.2.1",