gh-148210: fix incorrect _BINARY_OP_SUBSCR_DICT JIT optimization

[kumaraditya303]

Thanks to @Fidget-Spinner for suggesting the fix.

• Issue: Optimization of _BINARY_OP_SUBSCR_DICT is wrong. #148210

[corona10]

lgtm!

[markshannon]

The fix looks correct, but can we have a test?
This crashes on main:

>>> f = frozendict({"a":1})
>>> def test():
...     for _ in range(10_000):
...         f["a"]
>>> test()
Segmentation fault (core dumped)

[kumaraditya303]

The fix looks correct, but can we have a test?

Thanks for the reproducer, I added a test based on it.