gh-141938: Fix HTTPConnection being stuck in a dirty state when response.begin() raises exceptions

When response.begin() raises an exception other than ConnectionError
(such as TimeoutError), the outer exception handler calls
response.close() but not self.close(), leaving the HTTPConnection's
internal state stuck at _CS_REQ_SENT instead of being reset to _CS_IDLE.

This causes subsequent requests on the same connection to raise
CannotSendRequest even though the underlying socket has been closed.

The fix changes the outer exception handler to call self.close() instead
of just response.close(). This properly resets the connection state and
closes the socket, consistent with the inner ConnectionError handler.

Author: TotalyEnglizLitrate

Lib/http/client.py

@@ -1449,7 +1449,7 @@ def getresponse(self):
 
             return response
         except:
-            response.close()
+            self.close()
             raise
 
 try:

Misc/NEWS.d/next/Library/2025-11-29-00-52-37.gh-issue-141938.ZADQRl.rst

@@ -0,0 +1,4 @@
+Fix `http.client.HTTPConnection` to properly reset its internal state when
+reading the response raises an exception such as `TimeoutError`, ensuring
+the connection can be reused or raises appropriate errors on subsequent
+requests.