Bump eslint from 7.7.0 to 7.15.0

Bumps [eslint](https://github.com/eslint/eslint) from 7.7.0 to 7.15.0.
- [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/v7.7.0...v7.15.0)

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

package.json

@@ -70,7 +70,7 @@
   },
   "devDependencies": {
     "concurrently": "^5.1.0",
-    "eslint": "^7.4.0",
+    "eslint": "^7.15.0",
     "eslint-config-airbnb-base": "^14.2.0",
     "eslint-plugin-import": "^2.22.0",
     "istanbul": "^0.4.0",