Bump cross-env from 6.0.3 to 7.0.0

Bumps [cross-env](https://github.com/kentcdodds/cross-env) from 6.0.3 to 7.0.0.
- [Release notes](https://github.com/kentcdodds/cross-env/releases)
- [Changelog](https://github.com/kentcdodds/cross-env/blob/master/CHANGELOG.md)
- [Commits](https://github.com/kentcdodds/cross-env/compare/v6.0.3...v7.0.0)

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

package.json

@@ -33,7 +33,7 @@
   "dependencies": {},
   "devDependencies": {
     "autoprefixer": "^9.7.4",
-    "cross-env": "^6.0.3",
+    "cross-env": "^7.0.0",
     "get-folder-size": "^2.0.1",
     "html-minifier": "^4.0.0",
     "hugo-bin": "0.51.1",