fix: add missing paramiko.win_openssh (#8672)

stubs/paramiko/paramiko/win_openssh.pyi

@@ -0,0 +1,12 @@
+import sys
+
+if sys.platform == "win32":
+    PIPE_NAME: str
+
+    def can_talk_to_agent() -> bool: ...
+
+    class OpenSSHAgentConnection:
+        def __init__(self) -> None: ...
+        def send(self, data: bytes) -> int: ...
+        def recv(self, n: int) -> bytes: ...
+        def close(self) -> None: ...