ci: add retries for flaky Postgres tests

[dblythy]

New Pull Request Checklist

• I am not disclosing a vulnerability.
• I am creating this PR in reference to an issue.

Issue Description

Postgres can be flaky - adds 3 retries to postgres tests

Related issue: n/a

Approach

TODOs before merging

• A changelog entry is created automatically using the pull request title (do not manually add a changelog entry)

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• ❌ Please link an issue that describes the reason for this pull request, otherwise your pull request will be closed. Make sure to write it as Related issue: #123 in the PR description, so I can recognize it.

[codecov]

Codecov Report

Base: 93.96% // Head: 93.96% // Increases project coverage by +0.00% 🎉

Coverage data is based on head (1f26c50) compared to base (2a82d19).
Patch has no changes to coverable lines.

Additional details and impacted files

@@           Coverage Diff           @@
##            alpha    #8214   +/-   ##
=======================================
  Coverage   93.96%   93.96%           
=======================================
  Files         182      182           
  Lines       13744    13744           
=======================================
+ Hits        12914    12915    +1     
+ Misses        830      829    -1     

Impacted Files	Coverage Δ
src/Adapters/Files/GridFSBucketAdapter.js	80.32% <0.00%> (+0.81%)	⬆️

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[mtrezza]

Looks good! Is this ready for merge?

[dblythy]

Yep!

[mtrezza]

This is effectively covering the flakiness of the Postgres tests - practical but this will also make it unlikely that someone will fix the actual flakiness. So I'm actually not sure whether this is beneficial?

[dblythy]

Good point actually, if a test is added that is flaky, we will never know with this method

#7180