Bump eslint from 7.20.0 to 7.21.0 (#113)

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>

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

package.json

@@ -37,7 +37,7 @@
     "@typescript-eslint/parser": "^4.15.1",
     "@types/fs-extra": "^9.0.6",
     "@zeit/ncc": "^0.22.3",
-    "eslint": "^7.20.0",
+    "eslint": "^7.21.0",
     "eslint-plugin-github": "^4.1.1",
     "eslint-plugin-jest": "^24.1.5",
     "jest": "^26.6.3",