Bump eslint from 7.20.0 to 7.21.0

Bumps [eslint](https://github.com/eslint/eslint) from 7.20.0 to 7.21.0.
- [Release notes](https://github.com/eslint/eslint/releases)
- [Changelog](https://github.com/eslint/eslint/blob/master/CHANGELOG.md)
- [Commits](https://github.com/eslint/eslint/compare/v7.20.0...v7.21.0)

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

package.json

@@ -42,7 +42,7 @@
     "babel-eslint": "^10.1.0",
     "babel-loader": "^8.2.2",
     "css-loader": "^5.1.0",
-    "eslint": "^7.20.0",
+    "eslint": "^7.21.0",
     "eslint-config-airbnb-base": "^14.2.1",
     "eslint-loader": "^4.0.2",
     "eslint-plugin-import": "^2.22.1",