Bump eslint from 7.17.0 to 7.21.0

Bumps [eslint](https://github.com/eslint/eslint) from 7.17.0 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@v7.17.0...v7.21.0)

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

package.json

@@ -104,7 +104,7 @@
     "babel-eslint": "^10.1.0",
     "babel-jest": "^26.6.3",
     "babel-preset-gatsby": "^0.12.2",
-    "eslint": "^7.17.0",
+    "eslint": "^7.21.0",
     "eslint-config-standard": "^16.0.2",
     "eslint-plugin-import": "^2.22.0",
     "eslint-plugin-jest": "^24.1.5",