ext/session: fix missing zval_ptr_dtor for retval in PS_GC_FUNC(user)#21747

jorgsowa wants to merge 2 commits intophp:PHP-8.4php/php-src:PHP-8.4from

jorgsowa:fix/session-gc-retval-leakjorgsowa/php-src:fix/session-gc-retval-leakCopy head branch name to clipboard