Fix persist plugin expiry

[NorbertHeusser]

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[codecov]

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 ⚠️
test/unit/broker/subs_stubs.c	0.00%	3 Missing ⚠️
plugins/persist-sqlite/base_msgs.c	90.00%	1 Missing ⚠️
src/database.c	90.90%	1 Missing ⚠️

Additional details and impacted files

@@             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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