Unsoundness/inconsistency with to_real

[wintered]

11fb5c7

$ cvc5 -q --check-models bug.smt2
sat
$ z3 model_validate=true bug.smt2
unsat
$ cat bug.smt2
(declare-fun x () Real)
(assert (xor (is_int (to_real (* 2 x))) (<= 2 2)))
(check-sat)