fix(get_config): use SSHClient.connect() without algorithm overrides

The SSH console link works on this switch using plain paramiko
SSHClient.connect() with no disabled_algorithms and no Transport hacks.
Our previous approaches (Transport._preferred_kex, socket-level timeout)
were breaking the negotiation. Revert to the simple approach that works.

napalm_procurve/procurve.py

@@ -592,50 +592,32 @@ class ProcurveDriver(ConfigLifecycleMixin, SwitchDriver):
         Used as fallback when the REST API does not expose the config endpoint
         (e.g. HP 2530 / YA firmware with Mocana SSH).
 
-        Uses a raw socket with settimeout() so the timeout covers ALL phases of
-        the SSH handshake (TCP connect, banner, KEX, auth) — not just TCP connect.
-        This is the only reliable way to prevent a hanging KEX from blocking
-        indefinitely inside the poll task.
+        Uses SSHClient.connect() with the same approach as the netOrk SSH
+        console link (_paramiko_connect in _helpers.py) — no algorithm
+        overrides, plain password auth, 15-second banner timeout.
         """
-        import socket as _socket
-
         import paramiko
 
-        _FALLBACK_TIMEOUT = 8  # seconds — covers the entire SSH session
-
-        _LEGACY_KEX = [
-            "diffie-hellman-group1-sha1",
-            "diffie-hellman-group14-sha1",
-            "diffie-hellman-group14-sha256",
-        ]
+        _TIMEOUT = 15
 
         try:
-            sock = _socket.create_connection(
-                (self.hostname, self.port or 22),
-                timeout=_FALLBACK_TIMEOUT,
-            )
-            sock.settimeout(_FALLBACK_TIMEOUT)  # applies to all recv/send including KEX
-
-            transport = paramiko.Transport(sock)
-            transport.get_security_options().kex = _LEGACY_KEX
-            transport.connect(
+            client = paramiko.SSHClient()
+            client.set_missing_host_key_policy(paramiko.AutoAddPolicy())
+            client.connect(
+                hostname=self.hostname,
+                port=self.port or 22,
                 username=self.username,
                 password=self.password,
+                timeout=_TIMEOUT,
+                banner_timeout=_TIMEOUT,
+                auth_timeout=_TIMEOUT,
+                look_for_keys=False,
+                allow_agent=False,
             )
-
-            channel = transport.open_session()
-            channel.settimeout(_FALLBACK_TIMEOUT)
-            channel.exec_command("show running-config")
-
-            chunks: list[bytes] = []
-            while True:
-                data = channel.recv(4096)
-                if not data:
-                    break
-                chunks.append(data)
-
-            transport.close()
-            return b"".join(chunks).decode("utf-8", errors="replace")
+            _, stdout, _ = client.exec_command("show running-config", timeout=_TIMEOUT)
+            config = stdout.read().decode("utf-8", errors="replace")
+            client.close()
+            return config
         except Exception as exc:
             logger.warning("SSH config fallback failed for %s: %s", self.hostname, exc)
             return ""