Avoid unhandled promise rejection

[davimacedo]

According to the discussion on #5573 this PR removes the unhandled promise rejections during server initialization on prod.

[codecov]

Codecov Report

Merging #5578 into master will increase coverage by 0.01%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master    #5578      +/-   ##
==========================================
+ Coverage   94.03%   94.05%   +0.01%     
==========================================
  Files         129      129              
  Lines        9194     9199       +5     
==========================================
+ Hits         8646     8652       +6     
+ Misses        548      547       -1

Impacted Files	Coverage Δ
src/Options/index.js	100% <ø> (ø)	⬆️
src/ParseServer.js	97.18% <100%> (+0.83%)	⬆️
src/RestWrite.js	93.54% <0%> (-0.18%)	⬇️
...dapters/Storage/Postgres/PostgresStorageAdapter.js	96.9% <0%> (+0.08%)	⬆️

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