Fix httpx.Timeout configuration in PyPI proxy

backend/app/repositories/__init__.py

@@ -9,7 +9,6 @@ from .base import BaseRepository
 from .project import ProjectRepository
 from .package import PackageRepository
 from .artifact import ArtifactRepository
-from .tag import TagRepository
 from .upload import UploadRepository
 
 __all__ = [
@@ -17,6 +16,5 @@ __all__ = [
     "ProjectRepository",
     "PackageRepository",
     "ArtifactRepository",
-    "TagRepository",
     "UploadRepository",
 ]