Execute check field exists and update schema directly in SQL

[paulovitin]

Prevents the schema is overwritten in updates.

[codecov]

Codecov Report

Merging #3740 into master will decrease coverage by 0.02%.
The diff coverage is 100%.

@@            Coverage Diff            @@
##           master   #3740      +/-   ##
=========================================
- Coverage   90.22%   90.2%   -0.03%     
=========================================
  Files         114     114              
  Lines        7461    7461              
=========================================
- Hits         6732    6730       -2     
- Misses        729     731       +2

Impacted Files	Coverage Δ
...dapters/Storage/Postgres/PostgresStorageAdapter.js	95.31% <100%> (-0.14%)	⬇️
src/Adapters/Auth/meetup.js	84.21% <0%> (-5.27%)	⬇️
src/RestWrite.js	94.3% <0%> (ø)	⬆️

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[paulovitin]

Fix for this #3737

[flovilmart]

awesome @paulovitin ! Your PG skills shine bright! Thanks for taking care of those rough edges!