gh-106529: Fix subtle Tier 2 edge case with list iterator (#106756)

The Tier 2 opcode _IS_ITER_EXHAUSTED_LIST (and _TUPLE)
didn't set it->it_seq to NULL, causing a subtle bug
that resulted in test_exhausted_iterator in list_tests.py
to fail when running all tests with -Xuops.

The bug was introduced in gh-106696.

Added this as an explicit test.

Also fixed the dependencies for ceval.o -- it depends on executor_cases.c.h.