fix(test): remove unused cron import

src/cron/service.runs-one-shot-main-job-disables-it.test.ts

@@ -1,6 +1,6 @@
 import fs from "node:fs/promises";
 import path from "node:path";
-import { afterEach, describe, expect, it, vi } from "vitest";
+import { describe, expect, it, vi } from "vitest";
 import type { HeartbeatRunResult } from "../infra/heartbeat-wake.js";
 import type { CronJob } from "./types.js";
 import { CronService } from "./service.js";