chore: remove unused imports in setup-bun.mjs

Address github-code-quality bot comments.

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Co-Authored-By: Claude <[email protected]>

Author: ochafik

scripts/setup-bun.mjs

@@ -16,9 +16,8 @@ import {
   writeFileSync,
 } from "fs";
 import { join, dirname } from "path";
-import { execSync, spawnSync } from "child_process";
+import { spawnSync } from "child_process";
 import { fileURLToPath } from "url";
-import { createWriteStream } from "fs";
 import { get } from "https";
 import { createGunzip } from "zlib";