Bump @babel/preset-env from 7.7.4 to 7.7.6

Bumps [@babel/preset-env](https://github.com/babel/babel) from 7.7.4 to 7.7.6.
- [Release notes](https://github.com/babel/babel/releases)
- [Changelog](https://github.com/babel/babel/blob/master/CHANGELOG.md)
- [Commits](babel/babel@v7.7.4...v7.7.6)

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

package.json

@@ -26,7 +26,7 @@
   "devDependencies": {
     "@babel/cli": "7.7.4",
     "@babel/core": "7.7.4",
-    "@babel/preset-env": "7.7.4",
+    "@babel/preset-env": "7.7.6",
     "@babel/preset-typescript": "7.7.4",
     "@nextcloud/browserslist-config": "^1.0.0",
     "typescript": "3.7.2"