Bump dotenv from 6.2.0 to 8.1.0

Bumps [dotenv](https://github.com/motdotla/dotenv) from 6.2.0 to 8.1.0.
- [Release notes](https://github.com/motdotla/dotenv/releases)
- [Changelog](https://github.com/motdotla/dotenv/blob/master/CHANGELOG.md)
- [Commits](https://github.com/motdotla/dotenv/compare/v6.2.0...v8.1.0)

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

package.json

@@ -55,7 +55,7 @@
     "case-sensitive-paths-webpack-plugin": "2.2.0",
     "copy-webpack-plugin": "^5.0.3",
     "css-loader": "2.1.1",
-    "dotenv": "6.2.0",
+    "dotenv": "8.1.0",
     "dotenv-expand": "4.2.0",
     "eslint": "^6.1.0",
     "eslint-config-react-app": "^5.0.1",