Bump up PostgreSQL from 14 to 15

[YangJiao0817]

Fix #19512

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Comprehensive Summary of your change

Issue being fixed

Fixes #(issue)

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (ed4587b) 67.54% compared to head (965685a) 67.54%.

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #19789      +/-   ##
==========================================
- Coverage   67.54%   67.54%   -0.01%     
==========================================
  Files         991      991              
  Lines      109165   109165              
  Branches     2719     2719              
==========================================
- Hits        73737    73731       -6     
- Misses      31461    31465       +4     
- Partials     3967     3969       +2     

Flag	Coverage Δ
unittests	67.54% <ø> (-0.01%)	⬇️

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see 6 files with indirect coverage changes

[wy65701436]

lgtm