[3.11] [3.12] GH-106684: Close asyncio.StreamWriter when asyncio.StreamWriter is not closed by application (GH-107650) (GH-107656) (#107836)

[3.12] GH-106684:  Close `asyncio.StreamWriter` when `asyncio.StreamWriter` is not closed by application (GH-107650) (GH-107656)

GH-106684: raise `ResourceWarning` when `asyncio.StreamWriter` is not closed (GH-107650)
(cherry picked from commit 41178e4199)

(cherry picked from commit 7853c76906)

Co-authored-by: Kumar Aditya <kumaraditya@python.org>

Lib/asyncio/streams.py

@@ -391,6 +391,10 @@ class StreamWriter:
         self._transport = new_transport
         protocol._replace_writer(self)
 
+    def __del__(self):
+        if not self._transport.is_closing():
+            self.close()
+
 
 class StreamReader: