Fix ListProxy handling in _remove_circular_refs

The _remove_circular_refs function in salt.utils.data was trying to
reconstruct ListProxy objects by calling type(ob)(), but ListProxy.__init__
requires 3 arguments (target, parent_optsdict, key).

When grains data is processed with salt.utils.data.decode(), it calls
_remove_circular_refs which failed on ListProxy objects with:
  TypeError: ListProxy.__init__() missing 2 required positional arguments

Fixed by detecting ListProxy and converting to a regular list, consistent
with ListProxy.__deepcopy__() and __reduce_ex__() behavior.

Fixes: tests/pytests/scenarios/failover/multimaster/test_failover_master.py::test_minion_reconnection

Author: dwoz

salt/utils/data.py

@@ -196,7 +196,15 @@ def _remove_circular_refs(ob, _seen=None):
             for k, v in ob.items()
         }
     elif isinstance(ob, (list, tuple, set, frozenset)):
-        res = type(ob)(_remove_circular_refs(v, _seen) for v in ob)
+        # Handle ListProxy from OptsDict by converting to regular list
+        # ListProxy.__init__ requires special arguments, so we can't use type(ob)()
+        from salt.utils.optsdict import ListProxy
+
+        if isinstance(ob, ListProxy):
+            # Convert ListProxy to regular list (like __deepcopy__ does)
+            res = list(_remove_circular_refs(v, _seen) for v in ob)
+        else:
+            res = type(ob)(_remove_circular_refs(v, _seen) for v in ob)
     # remove id again; only *nested* references count
     _seen.remove(id(ob))
     return res