chore: Specify db adapter properly in postgres flaky test

[flovilmart]

Closes: #4294

[codecov]

Codecov Report

❗ No coverage uploaded for pull request base (master@0b69700). Click here to learn what that means.
The diff coverage is 100%.

@@            Coverage Diff            @@
##             master    #4630   +/-   ##
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  Coverage          ?   92.68%           
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  Files             ?      119           
  Lines             ?     8567           
  Branches          ?        0           
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  Hits              ?     7940           
  Misses            ?      627           
  Partials          ?        0

Impacted Files	Coverage Δ
src/Routers/PurgeRouter.js	84.61% <100%> (ø)

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[dplewis]

@flovilmart I know I've asked you this before but how do you go about fixing these flaky tests?

For instance how did you figure out this is a solution to

Failed: cannot perform operation: a background operation is currently running for collection parse._User

[flovilmart]

I didn't find a solution per se, just out of luck hopefull it will fix the flaky test ;) not sure ;)

[dplewis]

lol lets give it a shot