Revert ":arrow_up: Bump asgiref to 3.4.0 (encode#1100)" to avoid DeadLock

This reverts commit 312b186.

Author: tony

setup.py

@@ -46,7 +46,7 @@ def get_packages(package):
 env_marker_gte_37 = "python_version >= '3.7'"
 
 minimal_requirements = [
-    "asgiref>=3.4.0",
+    "asgiref>=3.3.4",
     "click>=7.0",
     "h11>=0.8",
     "typing-extensions;" + env_marker_below_38,

uvicorn/middleware/proxy_headers.py

@@ -16,7 +16,7 @@
     ASGISendCallable,
     HTTPScope,
     Scope,
-    WebSocketScope,
+    WebsocketScope,
 )
 
 
@@ -47,7 +47,7 @@ async def __call__(
         self, scope: Scope, receive: ASGIReceiveCallable, send: ASGISendCallable
     ) -> None:
         if scope["type"] in ("http", "websocket"):
-            scope = cast(Union[HTTPScope, WebSocketScope], scope)
+            scope = cast(Union[HTTPScope, WebsocketScope], scope)
             client_addr: Optional[Tuple[str, int]] = scope.get("client")
             client_host = client_addr[0] if client_addr else None