fix(get_config): close REST session before SSH fallback

HP ProCurve switches allow only 1 session per user. The REST API session
blocks SSH — closing it before the SSH attempt allows the connection.
_collect_config() is called last so all poll data is already collected.

napalm_procurve/procurve.py

@@ -569,7 +569,12 @@ class ProcurveDriver(ConfigLifecycleMixin, SwitchDriver):
             if result.get("running"):
                 return result
             # REST endpoint not available on this firmware (e.g. HP 2530 / YA series).
-            # Fall back to a temporary SSH connection to run show running-config.
+            # HP switches allow only one session per user — close the REST session
+            # first so the switch accepts the SSH connection.
+            try:
+                self._api._session.close()
+            except Exception:
+                pass
             running = self._get_config_via_ssh()
             return {"running": running, "startup": "", "candidate": ""}