Fix runner download from Gitea CDN

controller.py

@@ -26,6 +26,7 @@ RUNNER_URL = (
     "https://dl.gitea.com/gitea-runner/3.5.0/gitea-runner-3.5.0-linux-amd64"
 )
 RUNNER_SHA256 = "16dc5c89ad5ac5496369642f01ed29c9bb130a2512e16a8cc3b400d9d0bfea73"
+RUNNER_USER_AGENT = "ces-autodl-controller/1.0"
 RUNNER_LABELS = ["ubuntu-latest:host", "ces-ci:host", "gpu:host"]
 MODEL_FILES = [
     "config.json",
@@ -256,7 +257,8 @@ def ensure_runner(paths: Paths) -> Path:
     if paths.runner_cache.is_file() and sha256(paths.runner_cache) == RUNNER_SHA256:
         return paths.runner_cache
     paths.runner_cache.parent.mkdir(parents=True, exist_ok=True)
-    with urllib.request.urlopen(RUNNER_URL, timeout=300) as response, tempfile.NamedTemporaryFile(
+    request = urllib.request.Request(RUNNER_URL, headers={"User-Agent": RUNNER_USER_AGENT})
+    with urllib.request.urlopen(request, timeout=300) as response, tempfile.NamedTemporaryFile(
         dir=paths.runner_cache.parent, delete=False
     ) as temporary:
         while chunk := response.read(1024 * 1024):