Eslint integration (#2885)

* eslint integration

* ci & pre commit

* dev

* dev

* dev

tests/fetchStats.test.js

@@ -3,6 +3,7 @@ import axios from "axios";
 import MockAdapter from "axios-mock-adapter";
 import { calculateRank } from "../src/calculateRank.js";
 import { fetchStats } from "../src/fetchers/stats-fetcher.js";
+import { expect, it, describe, beforeEach, afterEach } from "@jest/globals";
 
 // Test parameters.
 const data_stats = {