`$IterationLimit` is not limiting evalation expansion

[rocky]

Description

$IterationLimit is not limiting expression expanion

How to Reproduce

$mathics -c 'Block[{$IterationLimit = 20}, yin := yang; yang := yin; yin]'

Output Given

Traceback (most recent call last):
  File "/tmp/.pyenv/versions/3.13.7/bin/mathics", line 7, in <module>
    sys.exit(main())
             ~~~~^^
  File "/tmp/Mathics3/mathics-core/mathics/__main__.py", line 591, in main
    result, evaluation = run_it()
                         ~~~~~~^^
  File "/tmp/Mathics3/mathics-core/mathics/__main__.py", line 583, in run_it
    return evaluation.parse_evaluate(expr, timeout=settings.TIMEOUT), evaluation
           ~~~~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/tmp/Mathics3/mathics-core/mathics/core/evaluation.py", line 168, in parse_evaluate
    return self.evaluate(expr, timeout)
           ~~~~~~~~~~~~~^^^^^^^^^^^^^^^
  File "/tmp/Mathics3/mathics-core/mathics/core/evaluation.py", line 271, in evaluate
    result = evaluate()
  File "/tmp/Mathics3/mathics-core/mathics/core/evaluation.py", line 244, in evaluate
    self.last_eval = query.evaluate(self)
                     ~~~~~~~~~~~~~~^^^^^^
  File "/tmp/Mathics3/mathics-core/mathics/eval/tracing.py", line 171, in wrapper
    result = func(expr, evaluation)
  File "/tmp/Mathics3/mathics-core/mathics/core/expression.py", line 585, in evaluate
    expr, reevaluate = expr.rewrite_apply_eval_step(evaluation)
                       ~~~~~~~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^
  File "/tmp/Mathics3/mathics-core/mathics/eval/tracing.py", line 171, in wrapper
    result = func(expr, evaluation)
  File "/tmp/Mathics3/mathics-core/mathics/core/expression.py", line 1360, in rewrite_apply_eval_step
    result = rule.apply(new, evaluation, fully=False)
  File "/tmp/Mathics3/mathics-core/mathics/core/rules.py", line 176, in apply
    self.pattern.match(
    ~~~~~~~~~~~~~~~~~~^
        expression,
        ^^^^^^^^^^^
    ...<5 lines>...
        },
        ^^
    )
    ^
...
  File "/tmp/Mathics3/mathics-core/mathics/core/pattern.py", line 387, in match_symbol
    pattern_context["yield_func"](pattern_context["vars_dict"], None)
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/tmp/Mathics3/mathics-core/mathics/core/rules.py", line 148, in yield_match
    new_expression = apply_fn(expression, vars, options, evaluation)
  File "/tmp/Mathics3/mathics-core/mathics/core/rules.py", line 279, in apply_rule
    new = self.replace.replace_vars(vars)
  File "/tmp/Mathics3/mathics-core/mathics/core/symbols.py", line 549, in replace_vars
    assert all(fully_qualified_symbol_name(v) for v in vars)
              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
RecursionError: maximum recursion depth exceeded

Expected behavior

$IterationLimit::itlim: Iteration limit of 20 exceeded.
$Aborted

Additional context

Discovered reading Wagner's Programming with the Mathematica Kernel. Example is taken from that.