Fix persist plugin expiry

[NorbertHeusser]

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[codecov[bot]]

Codecov Report

Attention: Patch coverage is 83.11688% with 13 lines in your changes are missing coverage. Please review.

Project coverage is 81.23%. Comparing base (09f0395) to head (fa6bb8b). Report is 4 commits behind head on develop.

Files	Patch %	Lines
test/unit/broker/persist_read_stubs.c	66.66%	8 Missing :warning:
test/unit/broker/subs_stubs.c	0.00%	3 Missing :warning:
plugins/persist-sqlite/base_msgs.c	90.00%	1 Missing :warning:
src/database.c	90.90%	1 Missing :warning:

Additional details and impacted files

```diff @@ Coverage Diff @@ ## develop #3016 +/- ## =========================================== + Coverage 81.20% 81.23% +0.02% =========================================== Files 188 188 Lines 31733 31767 +34 =========================================== + Hits 25769 25806 +37 + Misses 5964 5961 -3 ```

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