chore: bump eslint from 7.13.0 to 7.21.0

Bumps [eslint](https://github.com/eslint/eslint) from 7.13.0 to 7.21.0.
- [Release notes](https://github.com/eslint/eslint/releases)
- [Changelog](https://github.com/eslint/eslint/blob/master/CHANGELOG.md)
- [Commits](eslint/eslint@v7.13.0...v7.21.0)

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

package.json

@@ -58,7 +58,7 @@
     "config": "3.3.2",
     "conventional-changelog-cli": "2.1.0",
     "coveralls": "3.1.0",
-    "eslint": "7.13.0",
+    "eslint": "7.21.0",
     "eslint-config-xo": "0.33.1",
     "eslint-config-xo-react": "0.23.0",
     "eslint-config-xo-space": "0.25.0",