chore(deps): update dependency eslint to v7.21.0 (#979)

Co-authored-by: Renovate Bot <bot@renovateapp.com>

Author: renovate[bot]

package-lock.json

@@ -37,7 +37,7 @@
         "@typescript-eslint/eslint-plugin": "4.15.2",
         "@typescript-eslint/parser": "4.15.2",
         "babel-jest": "26.6.3",
-        "eslint": "7.20.0",
+        "eslint": "7.21.0",
         "husky": "5.1.1",
         "jest": "26.6.3",
         "lint-staged": "10.5.4",