ns-slapd crash in referint_get_config

[tbordaz]

Issue Description
Crash during teardown phase of tests/suites/plugins/referint_test.py::test_invalid_referint_log test

Package Version and Platform:

• all version

Steps to Reproduce
Steps to reproduce the behavior:

1. run tests/suites/plugins/referint_test.py::test_invalid_referint_log
2. check coredumpctl list

Expected results
It should not crash

[tbordaz]

4fe22ec..72c211b main
d18807f..1475453 389-ds-base-3.0
2bca5f9..2541f88 389-ds-base-2.5
951f391..17805fa 389-ds-base-2.4
a341ffe..fb6ef0a 389-ds-base-2.3
42c6e1a..8ec7279 389-ds-base-2.2
046f96e..c8407c1 389-ds-base-2.1
bb20b35..0c496fe 389-ds-base-2.0
98befc9..eccd7a3 389-ds-base-1.4.4
48b0bf0..afcae91 389-ds-base-1.4.3