[3.12] gh-111495: Add more tests on PyEval C APIs (#122789) (#128987) (#129023)

* Add Lib/test/test_capi/test_eval.py
* Add Modules/_testlimitedcapi/eval.c

(cherry picked from commit bf8b3746398ea756c97e3cf263d63ca3ce3a544e)

* gh-111495: Fix refleaks in test_capi.test_eval tests (#122851)

(cherry picked from commit b4a316087c32d83e375087fd35fc511bc430ee8b)
(cherry picked from commit 430ccbc009aa7a2da92b85d7aeadd39e1666e875)