[3.13] gh-130151: Fix reference leaks in `_hashlib.hmac_{new,digest}` (GH-130152) (#130491)

gh-130151: Fix reference leaks in `_hashlib.hmac_{new,digest}` (GH-130152)

* fix leak in `_hashlib.hmac_new`
* fix leak in `hmac_digest`
* fix exception type in `_hashlib.HMAC.copy`
(cherry picked from commit 071820113f11b8f6a21f98652d0840e10268114c)

Co-authored-by: Bénédikt Tran <10796600+picnixz@users.noreply.github.com>