Update dependency eslint to ^7.21.0

Author: renovate-bot

package-lock.json

@@ -40,7 +40,7 @@
     "@types/node": "^14.14.31",
     "@typescript-eslint/eslint-plugin": "^4.15.2",
     "@typescript-eslint/parser": "^4.15.2",
-    "eslint": "^7.20.0",
+    "eslint": "^7.21.0",
     "eslint-config-prettier": "^7.2.0",
     "eslint-plugin-jsdoc": "^32.2.0",
     "eslint-plugin-prettier": "^3.3.1",