test(core): download emulators concurrently

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tests/download_emulators.py

@@ -1,6 +1,7 @@
 #!/usr/bin/env python3
 import json
 import stat
+from concurrent.futures import ThreadPoolExecutor
 from http import HTTPStatus
 from pathlib import Path
 from typing import TypeAlias
@@ -135,10 +136,14 @@ def download_emulators_for_model(model: str) -> None:
     all_releases = get_all_releases()
     emus = get_emulators_for_model(model, all_releases)
 
-    for emu in emus:
+    def _run(emu: Emulator):
         emu.download()
         emu.set_as_executable()
 
+    with ThreadPoolExecutor(max_workers=8) as executor:
+        for _ in executor.map(_run, emus):
+            pass
+
 
 @click.command()
 @click.argument("model", type=click.Choice(ALL_MODEL_NAMES, case_sensitive=True))